EVALUATION OF LAYER MODULI IN FLEXIBLE PAVEMENT SYSTEMS USING NONDESTRUCTIVE AND PENETRATION TESTING METHODS By KWASI BADU-TWENEBOAH A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 1987 DEDICATED TO MY FAMILY, ESPECIALLY MY SISTER, ABENA KYEM AND GRANDFATHER, ATTA KWAME, FOR THEIR CONTINUAL PRAYERS, ENCOURAGEMENT AND SUPPORT DURING THE COURSE OF MY EDUCATION. "A MIND IS A TERRIBLE THING TO WASTE II ACKNOWLEDGMENTS I would like to express my gratitude to Dr. Byron E. Ruth, chairman of my supervisory committee, for his guidance, encouragement and con structive criticisms in undertaking this research work. I am also grateful to Drs. F. C. Townsend, J. L. Davidson, M. Tia, J. L. Eades, and D. P. Spangler for serving on my graduate supervisory committee. I consider myself honored to have had these distinguished men on my com mittee. I also owe sincere thanks to Dr. J. H. Schaub, chairman of the civil engineering department, for the many times he gave help during the course of my studies here, especially in my obtaining the grant award to participate in the 1986 APWA Congress in New Orleans, Louisiana. I would like to express my appreciation to the Florida Department of Transportation (FDOT) for providing the financial support, testing facilities, materials, and personnel that made this research possible. I would like to thank the many individuals at the Pavement Evaluation and Bituminous Materials Research sections of the Bureau of Materials and Research at FDOT who contributed significantly to the completion of this work. In particular, I am indebted to Messrs. W. G. Miley, Ron McNamara, Ed Leitner, Don Bagwell, and John Purcell for giving so generously of their time. A very special word of thanks goes to Dr. David Bloomquist for his significant contributions in conducting the in situ penetration tests and for his helpful suggestions, advice, and friendship. The assistance of Mr. Ed Dobson in the field work is also appreciated. I would also like to thank Dr. F. Balduzzi of the Institute of Foundation Engineering and Soil Mechanics of the Federal Institute of Technology, Zurich, Switzerland, for inviting me to the institute, and consequently helping me develop the interest to pursue active research and further studies. Last, but far from being the least, I would like to thank Ms. Candace Leggett for her expertise and diligent skill in typing this dissertation. iv TABLE OF CONTENTS Page ACKNOWLEDGMENTS ii LIST OF TABLES ix LIST OF FIGURES xi 11 ABSTRACT xx CHAPTER 1 INTRODUCTION 1 1.1 Background 1 1.2 Study Objectives 3 1.3 Scope of Study 4 2 LITERATURE REVIEW 6 2.1 Introduction 6 2.2 Elastic-Layer Theory 7 2.2.1 General 7 2.2.2 One-Layer System 8 2.2.3 Two-Layer System 9 2.2.4 Three-Layer System 10 2.2.5 Multilayered or N-Layered Systems 11 2.3 Material Characterization Methods 13 2.3.1 General 13 2.3.2 State-of-the-Art Nondestructive Testing 15 2.3.2.1 General 15 2.3.2.2 Static Deflection Procedures 16 2.3.2.3 Steady-State Dynamic Force- Deflection 21 2.3.2.4 Dynamic Impact Load Response 24 2.3.2.5 Wave Propagation Technique 29 2.3.3 NDT Data-Interpretation Methods 32 2.3.3.1 General 32 2.3.3.2 Direct Solutions 36 2.3.3.3 Back-Calculation Methods 41 2.3.4 Other In Situ Methods 44 v Page 2.4Factors Affecting Modulus of Pavement-Subgrade Materials 47 2.4.1 Introduction 47 2.4.2 Temperature 48 2.4.3 Stress Dependency 49 3 EQUIPMENT AND FACILITIES 55 3.1 Description of Dynaflect Test System 56 3.1.1 Description of Equipment 56 3.1.2 Calibration 59 3.1.3 Testing Procedure 59 3.1.4 Limitations 60 3.2 Description of the Falling Weight Deflectometer Testing System 60 3.2.1 The 8002 FWD 61 3.2.2 The 8600 System Processor 61 3.2.3 The HP-85 Computer 63 3.2.4 Testing Procedure 63 3.2.5 Advantages 64 3.3 BISAR Computer Program 64 3.4 Description of Cone Penetration Test Equipment 65 3.5 Marchetti Dilatometer Test Equipment 67 3.6 Plate Bearing Test 70 4 SIMULATION AND ANALYSES OF NDT DEFLECTION DATA 71 4.1 BISAR Simulation Study 71 4.1.1 General 71 4.1.2 Dynaflect Sensor Spacing 74 4.1.3 FWD Sensor Spacing 74 4.2 Sensitivity Analysis of Theretical NDT Deflection Basins 76 4.2.1 Parametric Study 76 4.2.2 Summary of Sensitivity Analysis 88 4.3 Development of Layer Moduli Prediction Equations. 91 4.3.1 General 91 4.3.2 Development of Dynaflect Prediction Equations.... 95 4.3.2.1 Prediction Equations for Ex 95 4.3.2.2 Prediction Equation for E£ for Thin Pavements 103 4.3.2.3 Prediction Equations for E3 105 4.3.2.4 Prediction Equations for E^ 108 4.3.3 Development of FWD Prediction Equations 110 4.3.3.1 Prediction Equations for E1 110 4.3.3.2 Prediction Equations for E£ Ill 4.3.3.3 Prediction Equations for E3 113 4.3.3.4 Prediction Equations for E^ 114 vi Page 4.4Accuracy and Reliability of NDT Prediction Equations.... 119 4.4.1 Prediction Accuracy of Dynaflect Equations 119 4.4.1.1 Asphalt Concrete Modulus, E: 119 4.4.1.2 Base Course Modulus, E2, for Thin Pavements 123 4.4.1.3 Stabilized Subgrade Modulus, E 123 4.4.1.4 Subgrade Modulus, E4 125 4.4.2 Prediction Accuracy of FWD Equations 127 4.4.2.1 Asphalt Concrete Modulus, E 127 4.4.2.2 Base Course Modulus, E2 129 4.4.2.3 Stabilized Subgrade Modulus, E3 132 4.4.2.4 Subgrade Modulus, E4 134 5 TESTING PROGRAM 136 5.1 Introduction 136 5.2 Location and Characteristics of Test Pavements 137 5.3 Description of Testingn Procedures 140 5.3.1 General 140 5.3.2 Dynaflect Tests 142 5.3.3 Falling Weight Deflectometer Tests 142 5.3.4 Cone Penetration Tests 144 5.3.5 Dilatometer Tests 145 5.3.6 Plate Loading Tests 145 5.3.7 Asphalt Rheology Tests 147 5.3.8 Temperature Measurements 151 6 ANALYSES OF FIELD MEASURED NDT DATA 153 6.1 General 153 6.2 Linearity of Load-Deflection Response 153 6.3 Prediction of Layer Moduli 169 6.3.1 General 169 6.3.2 Dynaflect Layer Moduli Predictions 171 6.3.3 FWD Prediction of Layer Moduli 174 6.4 Estimation of Ex from Asphalt Rheology Data 178 6.5 Modeling of Test Pavements 181 6.5.1 General 181 6.5.2 Tuning of Dynaflect Deflection Basins 182 6.5.3 Tuning of FWD Deflection Basins 205 6.5.4 Nonuniqueness of NDT Backcalculation of Layer Modul i 231 6.5.5 Effect of Stress Dependency 233 6.6 Comparison of NDT Devices 236 6.6.1 Comparison of Deflection Basins 238 6.6.2 Comparison of Layer Moduli 253 6.7 Analyses of Tuned NDT Data 265 6.7.1 General 265 6.7.2 Analysis of Dynaflect Tuned Data 266 vii Page 6.7.2.1 Comparison of Measured and Predicted Deflections 266 6.7.2.2 Development of Simplified Layer Moduli Equations 271 6.7.3Analysis of FWD Tuned Data 279 6.7.3.1 Comparison of Measured and Predicted Deflections 279 6.7.3.2 Development of Prediction Equations 282 7 INTERPRETATION OF IN SITU PENETRATION TESTS 288 7.1 General 288 7.2 Soil Profiling and Identification 289 7.3 Correlation Between ED and qc 292 7.4 Evaluation of Resilient Moduli for Pavement Layers 302 7.4.1 General 302 7.4.2 Correlation of Resilient Moduli with Cone Resistance 304 7.4.3 Correlation of Resilient Moduli with Dilatometer Modulus 308 7.5 Variation of Subgrade Stiffness with Depth 312 8 PAVEMENT STRESS ANALYSES 316 8.1 General 316 8.2 Short-Term Load Induced Stress Analysis 318 8.2.1 Design Parameters 318 8.2.2 Comparison of Pavement Response and Material Properties 319 8.2.3 Summary 330 9 CONCLUSIONS AND RECOMMENDATIONS 331 9.1 Conclusions 331 9.2 Recommendations 334 APPENDICES A FIELD DYNAFLECT TEST RESULTS 338 B FIELD FWD TEST RESULTS 354 C COMPUTER PRINTOUT OF CPT RESULTS 379 D COMPUTER PRINTOUT OF DMT RESULTS 406 E RECOVERED ASPHALT RHEOLOGY TEST RESULTS 432 F RECOMMENDED TESTING AND ANALYSIS PROCEDURES FOR THE MODIFIED DYNAFLECT TESTING SYSTEM 456 G PARTIAL LISTING OF DELMAPS1 COMPUTER PROGRAM 463 viii Page REFERENCES 478 BIOGRAPHICAL SKETCH 491 ix LIST OF TABLES Table Page 2.1 Summary of Deflection Basin Parameters 35 2.2 Summary of Computer Programs for Evaluation of Flexible Pavement Moduli from NOT Devices 42 4.1 Range of Pavement Layer Properties 73 4.2 Sensitivity Analysis of FWD Deflections for tx = 3.0 in 86 4.3 Sensitivity Analysis of FWD Deflections for t t and t3 87 4.4 Sensitivity Analysis of FWD Deflections for E = 600 ksi and tx = 3.0 in 89 4.5 Pavements with Dynaflect Ex Predictions Having More Than 10 Percent Error 121 4.6 Pavements with Dynaflect E2 Predictions Having More Than 10 Percent Error 124 4.7 Comparison of Actual and Predicted E Values for Varying tx 126 4.8 Prediction Accuracy of Equation 4.18--Error Distribution as a Function of tl 128 4.9 Prediction Accuracy of Equation 4.19--Error Distribution as a Function of tj 130 4.10 Pavements with Ex Predictions Having 15 Percent or More Error 131 4.11 Pavements with E2 Predictions Having 20 Percent or More Errors 133 5.1 Characteristics of Test Pavements 138 5.2 Summary of Tests Performed on Test Pavements 143 5.3 Plate Loading Test Results 148 x 5.4 Viscosity-Temperature Relationships of Recovered Asphalt from Test Pavements 149 5.5 Temperature Measurements of Test Pavement Sections 152 6.1 Typical Dynaflect Deflection Data from Test Sections.. 170 6.2 Typical FWD Data from Test Sections 172 6.3 Layer Moduli Using Dynaflect Prediction Equations 173 6.4 Layer Moduli Using FWD Prediction Equations 176 6.5 Comparison Between NDT and Rheology Predictions of Asphalt Concrete Modulus 180 6.6 Comparison of Field Measured and BISAR Predicted Dynaflect Deflections 183 6.7 Dynaflect Tuned Layer Moduli for Test Sections 203 6.8 Predicted Deflections from Tuned Layer Moduli 204 6.9 Comparison of Field Measured and BISAR Predicted FWD Deflections 206 6.10 FWD Tuned Layer Moduli for Test Sections 227 6.11 Predicted FWD Deflections from Tuned Layer Moduli 228 6.12 Comparison Between Re-Calculated and Tuned FWD Layer Moduli 230 6.13 Illustration of Nonuniqueness of Backcalculation of Layer Moduli from NDT Deflection Basin 232 6.14 Comparison of Deflections Measured at Different Load Levels 235 6.15 Comparison Between Tuned Layer Moduli and Applied FWD Load 237 6.16 Comparison of the Asphalt Concrete Modulus for the Test Sections 254 6.17 Comparison of the Base Course Modulus for the Test Sections 258 6.18 Comparison of the Subbase Modulus for the Test Sections 259 6.19 Comparison of the Subgrade Modulus for the Test Sections 260 XI 6.20 Ratios of Dynaflect Moduli to FWD Moduli for Test Sections... 262 6.21 Correlation Between Measured and Predicted FWD (9-kip Load) Deflections 281 7.1 Relationship Between Eq and qc for Selected Test Sections in Florida 298 7.2 Correlation of NDT Tuned Base Course Modulus (E2) to Cone Resistance 305 7.3 Correlation of NDT Tuned Subbase Modulus (E3) to Cone Resistance 306 7.4 Correlation of NDT Tuned Subgrade Modulus (E^) to Cone Resistance 307 7.5 Relationship Between Resilient Modulus, E^ and Cone Resistance, qc 308 7.6 Correlation of NDT Tuned Subbase Modulus to Dilatometer Modulus 309 7.7 Correlation of NDT Tuned Subgrade Modulus to Dilatometer Modulus 310 7.8 Relationship Between Resilient Modulus, E^ and Dilatometer Modulus, ED 311 7.9 Effect of Varying Subgrade Stiffness on Dynaflect Deflections on SR 26A 314 8.1 Material Properties and Results of Stress Analysis for SR 26B (Gilchrist County); a) Input Parameters for BISAR; b) Pavement Stress Analysis 320 8.2 Material Properties and Results of Stress Analysis for SR 24 (Alachua County); a) Input Parameters for BISAR; b) Pavement Stress Analysis 321 8.3 Material Properties and Results of Stress Analysis for US 441 (Columbia County); a) Input Parameters for BISAR; b) Pavement Stress Analysis 322 8.4 Material Properties and Results of Stress Analysis for SR 15C (Martin County); a) Input Parameters for BISAR; b) Pavement Stress Analysis 323 8.5 Material Properties and Results of Stress Analysis for SR 80 (Palm Beach County); a) Input Parameters for BISAR; b) Pavement Stress Analysis 324 8.6 Summary of Pavement Stress Analysis at Low Temperatures 326 xii 8.7 Effect of Increased Base Course Modulus on Pavement Response on SR 80; a) Input Parameters for BISAR; b) Pavement Stress Analysis 329 xm LIST OF FIGURES Figure Page 2.1 Well-Designed Pavement Deflection History Curve 18 2.2 Typical Annual Deflection History for a Flexible Pavement.... 20 2.3 Typical Output of a Dynamic Force Generator 22 2.4 Schematic Diagram of Impulse Load-Response Equipment 25 2.5 Characteristic Shape of Load Impulse 26 2.6 Comparison of Pavement Response from FWD and Moving-Wheel Loads, a) Surface Deflections; b) Vertical Subgrade Strains 28 2.7 Empirical Interpretation of Dynaflect Deflection Basin, a) Basin Parameters; b) Criteria 34 2.8 Dynaflect Fifth Sensor Deflection-Subgrade Modulus Relationship 40 2.9 Temperature Prediction Graphs, a) Pavements More Than 2 in. Thick; b) Pavements Equal to or Less Than 2 in. Thick 50 3.1 Typical Dynamic Force Output Signal of Dynaflect 57 3.2 Configuration of Dynaflect Load Wheels and Geophones in Operating Position 58 3.3 Schematic of FWD Load-Geophone Configuration and Deflection Basin 62 3.4 Schematic of Marchetti Dilatometer Test Equipment 69 4.1 Four-Layer Flexible Pavement System Model 72 4.2 Dynaflect Modified Geophone Positions 75 4.3 Typical Four-Layer System Used for the Sensitivity Analysis 77 xiv 4.4 Effect of Change of Ex on Theoretical FWD (9-kip Load) Deflection Basin 79 4.5 Effect of Change of E2 on Theoretical FWD (9-kip Load) Deflection Basin 80 4.6 Effect of Change of E on Theoretical FWD (9-kip Load) Deflection Basin 81 4.7 Effect of Change of E4 on Theoretical FWD (9-kip Load) Deflection Basin 82 4.8 Effect of Change of tj on Theoretical FWD (9-kip Load) Deflection Basin 83 4.9 Effect of Change of t2 on Theoretical FWD (9-kip Load) Deflection Basin 84 4.10 Effect of Change of t3 on Theoretical FWD (9-kip Load) Deflection Basin 85 4.11 Effect of Varying Subgrade Thickness on Theoretical FWD (9-kip Load) Deflection Basin 90 4.12 Variation in Dynaflect Deflection Basin with Varying E2 and E3 Values with tx = 3.0 in 93 4.13 Variation in Dynaflect Deflection Basin with Varying E3 and E4 Values with tx = 3.0 in 94 4.14 Relationship Between Ex and Dx D4 for tx = 3.0 in 96 4.15 Relationship Between Ex and Dx D4 for tx = 6.0 in 97 4.16 Relationship Between Ex and Dx D4 for tx = 8.0 in 98 4.17 Variation of K: with tx for Different E2 Values 100 4.18 Variation of K2 with tx for Different E2 Values 101 4.19 Relationship Between E2 and Dx D4 for tx = 1.0 in 104 4.20 Comparison of E4 Prediction Equations Using Modified Sensor 10 Deflections 109 4.21 Relationship Between E and FWD Deflections for Fixed ElS E2, and Eg Values with tx = 3.0 in 116 4.22 Relationship Between E and FWD Deflections for Fixed Ex, E2, and Eg Values with t: = 6.0 in 117 5.1 Location of Test Pavements in the State of Florida 139 xv 5.2 Layout of Field Tests Conducted on Test Pavements 141 6.1 Surface Deflection as a Function of Load on SR 26A 155 6.2 Surface Deflection as a Function of Load on SR 26C 156 6.3 Surface Deflection as a Function of Load on SR 24 157 6.4 Surface Deflection as a Function of Load on US 301 158 6.5 Surface Deflection as a Function of Load on US 441 159 6.6 Surface Deflection as a Function of Load on I-10A 160 6.7 Surface Deflection as a Function of Load on I-10B 161 6.8 Surface Deflection as a Function of Load on I-10C 162 6.9 Surface Deflection as a Function of Load on SR 715 163 6.10 Surface Deflection as a Function of Load on SR 12 164 6.11 Surface Deflection as a Function of Load on SR 15C 165 6.12 Surface Deflection as a Function of Load on SR 26B 166 6.13 Surface Deflection as a Function of Load on SR 15A 167 6.14 Surface Deflection as a Function of Load on SR 15B 168 6.15 Comparison of Measured and Predicted Dynaflect Deflections for SR 26AM.P. 11.912 186 6.16 Comparison of Measured and Predicted Dynaflect Deflections for SR 26BM.P. 11.205 187 6.17 Comparison of Measured and Predicted Dynaflect Deflections for SR 26CM.P. 10.168 188 6.18 Comparison of Measured and Predicted Dynaflect Deflections for SR 24M.P. 11.112 189 6.19 Comparison of Measured and Predicted Dynaflect Deflections for US 301M.P. 11.112 190 6.20 Comparison of Measured and Predicted Dynaflect Deflections for I-10AM.P. 14.062 191 6.21 Comparison of Measured and Predicted Dynaflect Deflections for I-10BM.P. 2.703 192 6.22 Comparison of Measured and Predicted Dynaflect Deflections for I-10CM.P. 32.071 193 xvi 6.23 Comparison of Measured and Predicted Dynaflect Deflections for SR-15A--M.P. 6.549 194 6.24 Comparison of Measured and Predicted Dynaflect Deflections for SR 15BM.P. 4.811 195 6.25 Comparison of Measured and Predicted Dynaflect Deflections for SR 715--M.P. 4.722 196 6.26 Comparison of Measured and Predicted Dynaflect Deflections for SR 715--M.P. 4.720 197 6.27 Comparison of Measured and Predicted Dynaflect Deflections for SR 12M.P. 1.485 198 6.28 Comparison of Measured and Predicted Dynaflect Deflections for SR 80Section 1 199 6.29 Comparison of Measured and Predicted Dynaflect Deflections for SR 80Section 2 200 6.30 Comparison of Measured and Predicted Dynaflect Deflections for SR 15CM.P. 0.055 201 6.31 Comparison of Measured and Predicted Dynaflect Deflections for SR 15C--M.P. 0.065 202 6.32 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 26A--M.P. 11.912 208 6.33 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 26BM.P. 11.205 209 6.34 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 26CM.P. 10.168 210 6.35 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 26CM.P. 10.166.... 211 6.36 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 24M.P. 11.112 212 6.37 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for US 301M.P. 21.585..... 213 6.38 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for US 441--M.P. 1.236 214 6.39 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for I-10AM.P. 14.062 215 6.40 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for I-10BM.P. 2.703 216 xv ii 6.41 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for I-10C--M.P. 32.071 217 6.42 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15A--M.P. 6.546 218 6.43 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15A--M.P. 6.549 219 6.44 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15B--M.P. 4.811 220 6.45 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 715M.P. 4.722 221 6.46 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 715M.P. 4.720 222 6.47 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 12M.P. 1.485 223 6.48 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15CM.P. 0.055 224 6.49 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15CM.P. 0.065 225 6.50 Comparison of Measured NDT Deflection Basins on SR 26C M.P. 10.166 239 6.51 Comparison of Measured NDT Deflection Basins on US 301 M.P. 21.585 240 6.52 Comparison of Measured NDT Deflection Basins on US 441 M.P. 1.237 241 6.53 Comparison of Measured NDT Deflection Basins on SR 12 M.P. 1.485 242 6.54 Comparison of Measured NDT Deflection Basins on SR 26B M.P. 11.205 243 6.55 Comparison of Measured NDT Deflection Basins on SR 15A M.P. 6.549 244 6.56 Comparison of Measured NDT Deflection Basins on SR 715 M.P. 4.722 245 6.57 Comparison of Measured NDT Deflection Basins on SR 26A M.P. 11.912 246 6.58 Comparison of Measured NDT Deflection Basins on SR 24 M.P. 11.112 247 xviii 6.59 Comparison of Measured NDT Deflection Basins on I-10A-- M.P. 14.062 248 6.60 Comparison of Measured NDT Deflection Basins on I-10B M.P. 2.703 249 6.61 Comparison of Measured NDT Deflection Basins on I-10C M.P. 32.071 250 6.62 Comparison of Measured NDT Deflection Basins on SR 15B M.P. 4.811 251 6.63 Comparison of Measured NDT Deflection Basins on SR 15C M.P. 0.055 252 6.64 Relationship Between Asphalt Concrete Modulus, E and Mean Pavement Temperature 256 6.65 Comparison of Dynaflect and FWD Tuned Layer Moduli 261 6.66 Relationship Between Predicted and Measured Dynaflect Modified Sensor 1 Deflections 267 6.67 Relationship Between Predicted and Measured Dynaflect Modified Sensor 4 Deflections 268 6.68 Relationship Between Predicted and Measured Dynaflect Modified Sensor 7 Deflections 269 6.69 Relationship Between Predicted and Measured Dynaflect Modified Sensor 10 Deflections 270 6.70 Relationship Between E (Using Equation 6.8) and D2 D^.... 274 6.71 Relationship Between E12 (Using Equation 6.9) and Dx D^.... 275 6.72 Relationship Between E3 and D^ D? 276 6.73 Relationship Between E4 and D1(J 277 6.74 Simplified Flow Chart of DELMAPS1 Program 280 6.75 Relationship Between E4 and FWD Dg and D? 287 7.1 Variation of qc and FR with Depth on SR 12 290 7.2 Variation of Eq and Kg with Depth on SR 12 291 7.3 Variation of qc and Eq with Depth on SR 26A 293 7.4 Variation of qc and Eq with Depth on SR 26C 294 7.5 Variation of qc and Eq with Depth on US 301 295 xix 7.6 Variation of qc and ED with Depth on US 441 296 7.7 Variation of qc and Eg with Depth on SR 12 297 7.8 Correlation of Eg with qc 300 xx Abstract of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy EVALUATION OF LAYER MODULI IN FLEXIBLE PAVEMENT SYSTEMS USING NONDESTRUCTIVE AND PENETRATION TESTING METHODS By Kwasi Badu-Tweneboah December 1937 Chairman: Byron E. Ruth Major Department: Civil Engineering A research study was conducted to develop procedures for the eval uation of layer moduli in flexible pavement systems using in situ non destructive (NDT) and penetration tests. The _Bitumen structure Analysi in Roads (BISAR) elastic layer computer program was used to simulate Dynaflect and Falling Weight Deflectometer (FWD) load-deflection response for typical flexible pavements in the state of Florida. A field testing program consisting of Dynaflect, FWD, cone penetration, Marchetti Dilatometer, and plate bearing tests was conducted on fifteen pavement sections in the state of Florida. Cores of the asphalt con crete pavement were collected for laboratory low-temperature rheology tests. This provided a reliable and effective method of predicting the asphalt concrete modulus. A modified Dynaflect geophone configuration and simplified layer moduli prediction equations which allow a layer-by-layer analysis of Dynaflect deflection measurements were developed. Multiple linear regression equations with relatively good prediction accuracy were obtained from analyses of FWD deflection data. Different layer moduli values were obtained from the Dynaflect and FWD deflection basins for the various test sections. The penetration tests provided means for identifying the soils and also assessing the variability in stratigraphy of the test sites. Good correlations between cone resistance, qc, and dilatometer modulus, Eg, for sandy soils and soils above the water table were obtained. Pavement layer moduli determined from NDT data were regressed to qc and Eg for the various layers in the pavement. The correlations were better with qc than with Eg, and also for the base and subbase layers than the variable subgrade layer. The penetration tests can be used to supple ment NDT evaluation of pavements especially in locating zones of weak ness in the pavement or underlying subgrade soils. The effects of moisture, temperature, and the properties of the asphalt binder on the performance and response characteristics of flexible pavements were demonstrated using short-term load-induced stress analyses on five of the test pavements. xxii CHAPTER 1 INTRODUCTION 1.1 Background In recent years, the use of layered elastic theory to evaluate and design highway and airfield pavements has become increasingly popular vis-a-vis existing empirical methods. The elastic layer approach, also called mechanistic analysis, has obvious advantages over empirical methods which are based on the correlation between the maximum deflec tion under a load and pavement performance. It allows a rational eval uation of the mechanical properties of the materials in the pavement structure. An essential part of the mechanistic process is determining real istic elastic modulus values for the various layers in the pavement structure. Current methods to determine the modulus of pavement materials include various laboratory testing procedures, destructive field tests, and in situ nondestructive tests (NDT). The problems associated with the simulation of in situ conditions such as moisture content, density, loading history and rate of loading of the pavement in the laboratory are well known and recognized. Destructive field tests, such as the California bearing ratio (CBR) and plate tests are expen sive, time-consuming, and generally involve trenching the pavement, which has to be subsequently repaired. Nondestructive testing generally involves applying some type of dynamic load or shock waves to the surface of the pavement and measuring 1 2 the response of the pavement. Among such methods are various seismic techniques and surface dynamic loading tests. The basic concept behind seismic or wave propagation techniques is the use of vibratory loads and the resulting identification and measurement of the waves that propagate through the media. These methods have not gained wide acceptance, partly because of the relative sophistication required in field opera tion and in the interpretation of test data. Surface loading tests generally involve the use of measured surface deflections to backcalculate the moduli of the pavement layers. Among the numerous types of devices used are the Dynaflect, Road Rater, and Falling Weight Deflectometer (FWD). Such techniques have gained wide spread popularity partly because they are simple, time-efficient, and relatively inexpensive, and partly because of their ability to model real traffic load intensities and durations. However, there are no direct theoretical solutions available at present to evaluate the various layer moduli of the pavement from the measured surface deflec tions which generally represent the overall combined stiffness of the layers. Instead, computerized iterative solutions, graphical solutions, and nomographs are currently used to backcalculate pavement layer moduli. All these techniques basically consist of using linear-elastic programs in which calculated versus measured deflections are matched by adjustment of pavement layer moduli E-values. Those methods which are based on iterative procedures may need a large amount of computer time to arrive at the correct moduli for the pavement materials. In some cases, the required computer may not be accessible (e.g., for direct field evaluation) or the expertise required may not be available. Also, due to the inherent problems associated 3 with iteration methods, unique solutions cannot be guaranteed and dif ferent sets of elastic moduli can produce results that are within the specified (deflection or layer moduli) tolerance. In addition, elastic layer programs generally assume an average (composite) modulus for the subgrade layer without regard to the variation of the underlying soil properties with depth. For sites with highly variable subgrade stiff nesses, it becomes very difficult to analytically match measured deflec tion basins using a composite modulus for the subgrade layer. There fore, there is a need to find a more viable way to determine the E- values of pavement materials for a rational mechanistic analysis. Recent advances in in situ testing in geotechnical engineering have led to improvements in the determination of important soil parameters such as strength and deformation moduli. Unfortunately, the application of the improved techniques to evaluate or design pavements has been very limited. The Marchetti Dilatometer test (DMT) offers significant pro mise for providing a reliable and economical method for obtaining in situ moduli of pavement layers, especially of the subgrade. There is also the potential of determining in situ moduli from the cone penetra tion test (CPT) since several correlations between different deformation moduli and cone resistance have been reported in the geotechnical liter ature. The CPT and DMT provide detail information on site stratifica tion, identification, and classification of soil types which makes them attractive tests for the evaluation and design of pavements. 1.2 Study Objectives The primary objective of this study is to develop procedures for the evaluation of material properties in layered pavement systems using 4 NDT deflection measurements. This includes the development of layer moduli prediction equations from NDT deflections. The secondary objective is to evaluate the feasibility of deter mining the modulus of pavement layers and underlying subgrade soils using in situ penetration tests and to evaluate the possible effects of stratigraphy, water table and underlying subgrade soil properties on surface deflections obtained from NDT. 1.3 Scope of Study This investigation is primarily concerned with predicting pavement layer moduli from nondestructive and penetration tests. It is hoped that this will lead to improvements in the determination of layer moduli for mechanistic evaluation and design of flexible pavement systems. The initial part of the study consisted of developing layer moduli predic tion equations from computer-simulated Dynaflect and FWD deflection data. A modified Dynaflect load-sensor configuration was utilized in the theoretical analysis. Field tests were conducted on fifteen pavement sections in the state of Florida. Tests conducted consisted of Dynaflect, FWD, elec tronic CPT, DMT, and plate bearing tests. Also, cores of asphalt con crete pavement were collected for laboratory low-temperature rheology tests. These were used to establish viscosity-temperature relationships of the recovered asphalts which were then used to predict the moduli of the asphalt concrete layers. The field measured NDT data were analyzed to establish layer moduli values for the test pavement sections. The layer moduli derived from the Dynaflect and FWD nondestructive tests were compared with each other 5 and correlated to the results of the penetration tests. Simplified layer moduli prediction equations were developed for the modified Dynaflect testing system. Five of the test pavements were selected for short-term load induced stress analysis using actual wheel loadings and low temperature conditions. The effects of age-hardened asphalt, soil type, moisture content, weak base course and subgrade characteristics on layer stiff nesses were evaluated to assess the stress-strain response of the different pavements. CHAPTER 2 LITERATURE REVIEW 2.1 Introduction A mechanistic pavement design procedure consists of analyzing the pavement on the basis of the predicted structural response (stresses, strains, and deflections) of the system to moving vehicle loads. Pave ment-layer thicknesses (surface, base, and subbase) are selected such that the predicted structural response would be acceptable for some desired number of load repetitions and under existing environmental conditions. This approach is consistent with the conditions established by Yoder and Witczak that for any pavement design procedure to be completely rational in nature total consideration must be given to three elements. These elements are (1) the theory used to predict failure or distress parameter, (2) the evaluation of the pertinent material properties necessary for the theory selected, and (3) the determination of the rela tionship between the magnitude of the parameter in question to the failure or performance level desired. (133, p. 24-25) In the last several years, a concentrated effort has been made to develop a more rational analysis and design procedures for pavements. For flexible or asphalt concrete pavements, layered (7,19,20) and finite element (33) theories have been used with some success to analyze pave ment response. The use of either theory requires that the materials that make up the pavement be suitably characterized. Layered and finite element theories use Young's modulus and Poisson's ratio to characterize 6 7 the stress-strain behavior of pavement materials. While some success has been made in developing design theories, their limitations must also be understood. Most pavement material responses differ from the assump tions of the theory used, and the "true" values of stress, strain or deflection may differ from the predicted levels. However, a great deal of engineering reliance is being placed upon the use of multilayered linear elastic theory (133) in which the elastic modulus is an important input parameter. The thesis presented here is aimed at determining realistic modulus values for the structural characterization of flexible pavement systems using layered elastic theory. This chapter reviews previous work on layer-system solutions, the methods of determining the elastic modulus of pavement-layer materials, and some important factors influencing the modulus of elasticity. 2.2 Elastic-Layer Theory 2.2.1 General The type of theory used in the analysis of a pavement-layered system is generally distinguished by reference to three properties of material behavior response (133). They are the relationship between stress and strain (linear or nonlinear), the time dependency of strain under constant stress level (viscous or nonviscous), and the degree to which the material can rebound or recover strain after stress removal (plastic or elastic). These concepts have been clearly elucidated by Yoder and Witczak (133). Considerable effort has been expended to analyze pavement response using the above concepts. For example, the finite element method (33), elastic-layer analysis based on Burmister's 8 theory (18,19,20) and the visco-elastic layer analysis (7) are all based on these three properties of material behavior. As previously noted, the type of theory most widely used at the present time is the multilayered linear elastic theory. The development of multilayered elastic solutions is presented below. 2.2.2 One-Layer System The mathematical solution of the elastic problem for a concentrated load on a boundary of a semi-infinite body was given by Boussinesq in 1885 (13). His solution was based on the assumption that the material is elastic, homogeneous, and isotropic. Boussinesq's equation (133; p. 28) indicates that the vertical stress is dependent on the depth and radial distance and is independent of the properties of the transmitting medium. There are several limitations of this solution when applied to pavements. For example, the type of surface loading usually encountered in flexible pavements is not a point load but a load which is distri buted over an elliptical area (133). Further work with the Boussinesq equation expanded the solutions for a uniformly distributed circular load by integration. Newmark (85) developed influence charts for determination of stresses in elastic soil masses. The charts are widely used in foundation work. Love (60) used the principle of superposition to extend Boussinesq's solution to solve for a distributed load on a circular area. Foster and Ahlvin (36) presented charts for computing vertical stress, horizontal stress, and vertical elastic strains due to circular loaded plates, for a Poisson's ratio of 0.5. This work was subsequently refined by Ahlvin and Ulery (4) to allow for an extensive solution of the complete pattern of 9 stress, strain, and deflection at any point in the homogeneous mass for any value of Poisson's ratio. Although most asphalt pavement structures cannot be regarded as being homogeneous, the use of these solutions are generally applicable for subgrade stress, strain and deflection studies when the modular ratio of the pavement and subgrade is close to unity. This condition is probably most exemplified by conventional flexible granular base/subbase pavement structures having a thin asphalt concrete surface course (133). Normally, in deflection studies for this type of pavement, it is assumed that the pavement portion (above the subgrade) does not contribute any partial deflection to the total surface deflection. 2.2.3 Two-Layer System Since Boussinesq's solution was limited to a one-layer system, a need for a generalized multiple-layered system was recognized. Moreover, typical flexible pavements are composed of layers such that the moduli of elasticity decrease with depth (133). The effect is to reduce stresses and deflections in the subgrade from those obtained for the ideal homogeneous case. Burmister (18,19,20) established much of the ground work for the solution of elastic layers on a semi-infinite elastic layer. Assuming a continuous interface, he first developed solutions for two layers, and he conceptually established the solution for three-layer systems. The basic assumption made was full continuity between the layers, which implies that there is no slippage between the layers. Thus, Burmister assumed that the strain in the bottom of one layer is equal to the strain at the top of the next layer, but the stress levels in the two 10 layers will differ as a function of the modulus of elasticity of each layer. 2.2.4 Three-Layer System Although Burmister's work provided analytical expressions for stresses and displacements in two- and three-layer elastic systems, Fox (38) and Acum and Fox (2) produced the first extensive tabular summary of normal and radial stresses in three-layer systems at the intersection of the plate axis with the layer interfaces. Jones (52) and Peattie (89) subsequently expanded these solutions to a much wider range of solution parameters. Tables and charts for the various solutions can be found in Yoder and Witzcak (133) and Poulos and Davis (92). It should be noted that the figures and tables for stresses and displacements have been developed, respectively, for Poisson's ratios of 0.5 and 0.35, for all layers, and on the assumption of perfect friction at all interfaces. Hank and Scrivner (42) presented solutions for full continuity and zero continuity between layers. Their solutions indicate that the stresses in the top layer for the frictionless case (zero continuity) are larger than the stresses presented for the case of full continu ity. In an actual pavement, the layers are very likely to develop full continuity; hence, full continuity between layers should probably be assumed. Schiffman (100) extended Burmister's solution to include shear stress at the surface for a three-layer system. Mehta and Veletsos (73) developed a more general elastic solution to a system with any number of loads. They extended the solution presented by Burmister to include tangential forces as well as normal forces. 11 2.2.5 Multilayered or N-Layered Systems A general analysis of a multilayered system under general condi tions of surface loading or displacement, or both was developed indepen- dently by Schiffman (99) and Verstraeten (125). Schiffman (99) con sidered the general solutions for stresses and displacements due to non- uniform surface loads, tangential surface loads, and slightly inclined loads, but no numerical evaluations were presented. Verstraeten (125) presented a limited analysis of the four-layered elastic problem. He first derived expressions for the stresses and displacements for the general case and performed numerical calculations for the particular case of four-layered systems with continuous interfaces. The analysis by Verstraeten included not only a uniform normal surface stress, but also two types of surface shear stresses: (1) uniform one-directional shear stress and (2) a uniform centripetal shear stress. Recently, the Chevron Research Corporation (74) and the Shell Oil Company (32) have developed computer programs for multilayered solutions of the complete state of stress and strain at any point in a pavement structure. Notable programs of interest are the BISTRO and BISAR pro grams by Shell (32), and the various forms of CHEVRON program by the Chevron Research Corporation. These computer solutions are essentially an extension of Burmister's work that permit the analysis of a structure consisting of any number of layers supported by a semi-infinite sub grade, and under various loading conditions. In reality, it is only the CHEVRON N-LAYER program (74) which is suitable for any number of layers. All the others are restricted to a maximum number of layers. BISAR (32), for example, can handle nine pavement sub-layers of known thick nesses plus the semi-infinite subgrade or bottom layer. 12 Several investigators have verified the validity of Burmister's theory with the actual mechanical response of flexible pavements. Foster and Fergus (37) have compared the results of extensive test measurements on a clayey silt subgrade to theoretical stresses and deflections based on Burmister's theory and reported satisfactory agreement. The discrepancy between actual and theoretical stresses and displacements can be mainly attributed to the assumption of a homoge neous and isotropic material, the rate-dependent behavior of some materials such as asphalt, and a circular loaded area representing the wheel load. Nielsen (86) has made a detailed study in this area. His review of the magnitude and distribution of stresses within a layered system revealed regions where vertical and shearing stresses were criti cal. His studies concluded that the layered-elastic theory is in every respect consistent and that it is possible to establish fundamental patterns of pavement performance based upon this theory. This suggests that the elasticity theory could be used more extensively. The moderators of the Fifth International Conference on the Struc tural Design of Asphalt Pavements (76) concluded that the use of linear elastic theory for determining stresses, strains, and deflections is reasonable as long as the time-dependent and nonlinear response of the paving materials are recognized. They noted that the papers presented at the conference confirmed that multilayer elastic models generally yield good results for asphalt concrete pavements. Barksdale and Hicks (10) compared the multilayered elastic approach with the finite element method and recommended the use of the former for pavement analysis since only two variables are needed (modulus and Poisson's ratio). Pichumani (91) used the BISAR computer program for 13 the numerical evaluation of stresses, strains, and displacements in a linear elastic system. He demonstrated that predicted vertical, radial, and shear stress distribution were noticeably affected by slight changes in the assumed material moduli. Pichumani's work demonstrated the need for proper and extensive material characterization. 2.3 Material Characterization Methods 2.3.1 General The use of multilayered elastic theory has provided the engineer with a rational and powerful basis for the structural design of pave ments, for pavement evaluation, and for overlay design. In this theory, the complete stress, strain, and displacement pattern for a material needs only two material properties for characterization, namely the elastic modulus (E), and the Poisson's ratio (u). Generally, the effect of Poisson's ratio is not as significant as the effect of the modulus (133, pp. 280-282; 88; 59, p. 160). Thus, E is an important input parameter for pavement analysis using the layer theory. Many tests have been devised for measuring the elastic modulus of paving materials. Some of the tests are arbitrary in the sense that their usefulness lies in the correlation of their results with field performance. To obtain reproducible results, the procedures must be followed at all times. The various possible methods for determining the elastic modulus of pavement materials include laboratory tests, destruc tive field tests, and in situ nondestructive tests. Laboratory methods consist of conducting laboratory testing on either laboratory-compacted specimens or undisturbed samples taken from the pavement. Yoder and Witzcak (133) describe various laboratory 14 testing methods with the diametral resilient modulus test (8), indirect tension test (9), and the triaxial resilient modulus test (1) being the most popular. The latter is useful for unbound materials such as base course and subgrade soils, while the other two are for bound materials like asphalt concrete and stabilized materials. Monismith et al. (78) studied the various factors that affect laboratory determination of the moduli of pavement systems. They concluded that . . it is extremely difficult to obtain the same conditions that exist in the road materials (mois ture content, density, etc.) and the same loadings (including loading history) in the laboratory as will be encountered in situ. . Thus the best method of analysis would appear to be to determine an equivalent modulus which when substituted into expressions derived from the theory of elasticity, will give a reasonable estimate of the probable deformation. (78, p. 112) Destructive field tests include, among others, several different plate load tests (8) and the California Bearing Ratio (CBR) test (8). These tests require trench construction and subsequent repair of the pavement, and like the laboratory test methods, usually call for an elaborate and costly testing program. The delays associated with such programs are prohibitive especially for routine pavement analysis studies. The third method involves the extraction of pavement-layer proper ties from in situ nondestructive testing (NDT). NDT methods have gained wide popularity in the last few decades because of their ability to collect data at many locations on a highway or airfield in a short time. Therefore, a great deal of research effort has been concentrated on this area. A review of the various types of NDT equipment available and the associated interpretation tools is presented below. 15 2.3.2 State-of-the-Art of Nondestructive Testing 2.3.2.1 General. Nondestructive testing (NDT) consists of making nondestructive measurements on a pavement's surface and inferring from the responses the in situ characteristics related to the structural ade quacy or loading behavior (79). Among such methods are various seismic techniques (associated with time measurements) and surface loading tests (associated with deflection measurements). The latter is more popular because surface deflection is the most easily measured structural response of a pavement. The idea of using deflection measurements to evaluate the structural integrity of pavements dates back to 1938 when the California Division of Highways used electrical gages implanted in roadways to measure displacements induced by truck loads (134). There are currently several NDT procedures being used for pavement investigations. Each of the procedures can be placed into one of the following four general classes: 1. Static force-deflection, 2. Steady-state (vibratory) dynamic force-deflection, 3. Dynamic impulse force-deflection, and 4. Wave propagation. As their names imply, the first three categories are associated with deflection measurements due to application of force or load. The fourth category--wave propagationmeasures the length and velocity of force- induced waves traveling through the pavement system. A detailed description and evaluation of many of these NDT devices and procedures has been presented by Bush (21), Moore et al. (79), and Smith and Lytton (109). In the following pages, a brief description of the principles involved and equipment available for each class will be presented. 16 2.3.2.2 Static Deflection Procedures. Measurement systems that determine the pavement response to slowly applied loads are generally termed static deflection systems. In these systems, the loading, methods may consist of slowly driving to or from a measurement point with a loading vehicle, or by reacting against a stationary loading frame. The maximum resilient or recoverable deflection at the surface of the pave ment is measured. The most commonly used equipment in this class is the various forms of the Benkelman beam devices. Other equipment that had been used include the plate bearing test (8), Dehlen Curvature Meter, Traveling Deflectometer, Lacroix-LCPC Deflectograph, and the French Curviameter. The last three devices are essentially automation of the Benkelman beam principle. The French Curviameter, for example, measures both the deflection and curvature of the pavement, under an 18-kips rear axle load, with tire pressure maintained at 100 psi (24). Most of the automated devices have been used widely in Europe and other parts of the world, except for the Traveling Deflectometer which was built for the California Department of Transportation and has been in use by that agency for several years (109). The major advantages of the static deflection procedures are the simplicity of the equipment and the large amount of data that has been accumulated with these devices. The most serious problem with this type of measurement technique is the difficulty in obtaining an immovable reference point for making the deflection measurements. This makes the absolute accuracy of this type of procedure questionable. In addition, since most of the devices generally measure a single (maximum) 17 deflection only, it is impossible or difficult to determine the shape and size of the deflection basin. In spite of their shortcomings, the large amount of data developed using static deflection techniques makes such procedures an important part of structural pavement evaluation. For this reason, several inves tigators have attempted deflection comparison and correlations from the static devices with those measured by the dynamic devices. The following is a list of concepts developed from the deflection response of a pavement using static NDT (79): 1. For adequately designed pavements, the deflections during the same season of the year remain approximately constant for the life of the pavement. 2. There is a tolerable level of deflection that is a function of traffic type, volume and the structural capacity of the pavement as determined by the pavement's structural section. This tolerable level of deflection can be established through the use of fatigue characteristics of the pavement structure. 3. Overlaying of a pavement will reduce its deflection. The thickness required to reduce the deflection to a tolerable level can be esta- blished. 4. The deflection history of a well-designed pavement undergoes three phases in its behavior (71). A typical curve representing these phases is shown in Figure 2.1. a. In the initial phase, immediately after construction, the pave ment structure consolidates and the deflection shows a slight decrease. DEFLECTION Initial Phase Functional Phase TRAFFIC Failure Phase Figure 2.1 Wei 1-Designed Pavement Deflection History Curve (71) 19 b. During the functional or service phase, the pavement carries the anticipated traffic without undue deformation and the deflection remains fairly constant or shows a slight decrease. c. The failure phase occurs as a result of both traffic and envi ronmental factors. In this phase the deflection increases rapidly and there is a rapid deterioration resulting in failure of the pavement structure. 5. The deflection history of a pavement system varies throughout the year due to the effects of frost, temperature, and moisture. A typical annual deflection history of a pavement subjected to frost action, as shown in Figure 2.2, can be divided into the following four periods (103): a. The period of deep frost when the pavement is the strongest. b. The period during which the frost is beginning to disappear from the pavement structure. During this period, the deflection rises rapidly. c. The period during which the water from the melting frost leaves the pavement structure and the deflection begins to drop. d. The period during which the deflection levels off with a general downward trend as the pavement structure continues to slowly dry out. 6. For a given flexible pavement structure it is generally known that the magnitude of the deflection increases with an increase in the temperature of the bituminous surfacing material. This is due to a decrease in the stiffness of the bituminous surfacing. The effect of temperature varies with the stiffness of the underlying layers. As the stiffness of the underlying layers increases, the effect of DEFLECTION MONTH Figure 2.2 Typical Annual Deflection History for a Flexible Pavement (103) 21 an increase in temperature on deflection of the total structure decreases. 2.3.2.3 Steady-State Dynamic Force-Deflection. Essentially, all steady-state dynamic deflection measurement systems induce a steady state sinusoidal vibration in the pavement with a dynamic force genera tor. The dynamic force is superimposed on the weight of the force gen erator, resulting in a variation of force with time as shown in Figure 2.3. The magnitude of the peak-to-peak dynamic force is less than twice the static force to insure continuous contact of the vibrator with the pavement (79). This means there must always be some amount of dead weight or static force applied. As the dynamic peak-to-peak loading is increased, this preload must also be increased (109). Deflections are usually measured with inertial motion sensors. For pure sinusoidal motions at any fixed frequency, the output of such sen sors is directly proportional to deflection. Thus, to measure deflec tion it is only necessary to determine the calibration factor (output per unit of deflection) for the measurement frequency. In general, either an accelerometer or a velocity sensor may be used to measure deflections. The latter type is commonly called a geophone and is the type normally employed in dynamic deflection measurements. There are several different types of steady-state dynamic deflec tion equipment that are currently being used for nondestructive struc tural evaluation of pavements. Only two of them have been used exten sively and are available commerciallythe Dynaflect and the Road Rater. The others have been designed and constructed by agencies involved in pavement research, namely the U.S. Army Waterways Experiment Station (WES), the Federal Highway Administration (FHWA), the Illinois Figure 2.3 Typical Output of a Dynamic Force Generator (79) 23 Department of Transportation, and the Koninklijke/Shel1 Laboratorium, Amsterdam, Holland. Detailed descriptions of the various vibratory equipment can be found in References 21, 79, 109. The Dynaflect was used in this study and a description of the device will be given later in this report. When one considers the difficulty in obtaining a reference point for deflection measurements, the real advantage of a steady-state dyna mic deflection measurement system becomes apparent. An inertial refer ence can be employed to measure dynamic deflections. That is, the mag nitude of the deflection change (the peak-to-peak value) can be compared directly to the magnitude of the dynamic force change (peak-to-peak value). For a given value of dynamic force, the lower the deflection, the stiffer the pavement is (79). Although the dynamic response of a pavement system approaches its static (or elastic) response at low frequencies, exactly what value of driving frequency is low enough to determine the elastic characteristics of a pavement is somewhat questionable. As the driving frequency be comes low it becomes difficult to generate dynamic forces and the output of inertial motion sensors becomes very small. These factors combine to make it difficult to obtain accurate low frequency dynamic deflection measurements (79). Other technical limitations of vibratory equipment include the need for a heavy static preload for the heavier devices and the nonuniform loading configurations (109). The deflection measurements that result represent the stiffness of the entire pavement section. Although some significant accomplishments have been made in separating the effects of major parts of the pavement structure, the separation of the effects of all of the various 24 components of the structure with deflection basin measurements has not yet been accomplished (63). The study presented herein is aimed at developing an approach that would allow a layer-by-layer analysis of the Dynaflect vibratory deflection basin. 2.3.2.4 Dynamic Impact Load Response. Essentially, all impact load testing methods deliver some type of transient force impulse to the pavement surface and measure its transient response. The equipment uses a weight that is lifted to a given height on a guide system and is then dropped. Figure 2.4 illustrates this schematically. By varying the mass of the falling weight or the drop height or both, the impulse force can be varied. The width or duration of the loading pulse (loading time) is controlled by the buffer characteristics, Figure 2.4, and it closely approximates a half-sine wave (Figure 2.5). The duration of the force is nominally 25-30 msec, Figure 2.5, which approximates the load duration of a vehicle traveling 40 to 50 mph (123). The peak magnitude of the force can be determined approximately by equating the initial potential energy of the system to the stored strain energy of the springs (buffer system) when the mass is momentarily brought to rest (11,105). Thus F = (2Mghk)1/z Eqn. 2.1 where M = mass of the falling weight, h = drop height, k = spring constant, and g = acceleration due to gravity. 25 ' / / / / / s s s \ \ \ *///// \ s s s \ \ ///// /////# N N \ N S S ////// \ S N S N S /////# Figure 2.4 Schematic Diagram of Impulse Load-Response Equipment (105) Figure 2.5 Characteristic Shape of Load Impulse (105) 27 The response of the pavement to the impulse loading is normally measured with a set of geophones placed at varying radial distances from the center of the plate. These deflection measurements can, in princi ple, be used to characterize the structural properties of the pavement layers. Three manufacturers currently market impulse testing equipment in the United States. These are the Dynatest, KUA3 and Phoenix falling- weight deflectometers. The Dynatest falling-weight deflectometer (FWD) is the most widely used impulse loading device in North America and Europe (109). Its newest version--the Dynatest 8000 FWD testing system--was used in this study and will be described later in this report. Other experimental impulse testing devices have been evaluated by Washington State University and Cornell Aeronautical Laboratory (79). The impulse testing machines have several advantages over other NDT instruments. The magnitude of the force can be quickly and easily changed to evaluate the stress sensitivity of the pavement materials being tested. Perhaps the greatest advantage is the ability to simulate vehicular loading conditions. Several investigators (11,35,46) have compared pavement response in terms of stresses, strains, and deflec tions from an FWD-imposed load to the response of a moving wheel load. All these comparisons have shown that the response to an FWD test is quite close to the response of a moving wheel load with the same load magnitude. Figure 2.6 shows such an example of pavement response com parison. However, the deflection basin produced by an impulse loading device is symmetrical about the load and Lytton et al. (63) have argued that the deflection basin under a moving wheel is not symmetrical about the 28 a) Surface Deflections 600 Q ^g 400 DC c/> EL go 200 b DC I LL. DC LLI > 0 / / / / / / o / O o / A D 9* / / 0 200 400 600 VERTICAL STRAIN (x lO"6) FROM MOVING WHEEL LOAD b) Vertical Subgrade Strains Figure 2.6 Comparison of Pavement Response from FWD and Moving-Wheel Loads (35) 29 load in any pavement structure. Thus, the impulse load of a FWD is not an exact representation of a moving wheel load. Moreover, the response from the impact testing technique is similar to other types of dynamic deflection testing in the sense that it represents characterization of the entire structure. The technique does not provide information that readily separates the effects of its various layers. Finally, the parameters that cause plastic deformation in the structure are not readily determinable from impact testing (79). 2.3.2.5 Wave Propagation Technique. Wave propagation provides methods for the determination of the elastic properties of individual pavement layers and subgrades. Unlike the three previous methods of NOT, these methods are not concerned with the deflection response of the pavement. Rather, they are concerned with the measurement of the velo city and length of the surface waves propagating away from the load surface (127). There are two basic techniques for propagating waves through pave ment structures: (1) steady-state vibration tests and (2) seismic (impulse) tests. Generally, three types of waves are transmitted when a pavement surface is subjected to vibration. These are 1. Compression or primary (P) waves, 2. Shear (S) waves, and 3. Rayleigh (R) waves. The P and S waves are body waves while the R wave is a surface wave. Raleigh waves are the dominant waves found in the dissipation of energy input from a vibrator on a semi-infinite half-space (75). Also, because P and S waves attenuate rapidly with radial distance from the vibration 30 source, R waves are the typical waves measured in the wave propagation technique. Wave propagation theory is based upon the fact that in a homoge neous isotropic half space subjected to an external disturbance, waves travel at velocities that may be expressed as (59, p. 153; 79; 127) V, £) )/2 Eqn. 2.2a p 2(1 + u)p v = ( HV-J1.) )x/2 Eqn. 2>2b P p(l + y)(l 2y) VR = aV$ Eqn. 2.2c where Vs = shear wave velocity, Vp = compression wave velocity, Vr = Rayleigh wave velocity, G = shear modulus, E = Young's modulus, y = Poisson's ratio, p = mass density, and a is a function of Poisson's ratio and varies from 0.875 for y = 0 to 0.995 for y = 0.5. In general, R and S waves are not particularly dependent on Poisson's ratio, but the value of compression wave velocity is strongly dependent on Poisson's ratio (59,79). Field test procedures for the wave propagation measurements involve two general types of tests. Raleigh wave velocities are determined from 31 steady-state vibratory pavement responses and compression wave veloci ties are measured from impulse (seismic) tests. The former usually follows procedures developed by researchers at the Royal Dutch Shell Laboratory (43,53,93), the British Road Research Laboratory (79), and the Waterways Experiment Station (79). They utilized a mechanical vibrator for low-frequency vibrations (5-100 Hz) and a small electro magnetic vibrator for the high-frequency work (43,53). The general procedure currently in use is to place the vibrator on the pavement surface and set the equipment in operation at a constant frequency. Details of the procedure can be found in Reference 79. Seismic tests may be conducted to determine the velocity of com pression waves, which can be used with the shear wave (or Rayleigh wave) velocity to compute Poisson's ratio. One such method is the hammer- impulse technique in which the pavement is struck with a light hammer and the resultant ground motion is observed at one or more points with horizontal motion geophones. However, this method is only good for soils where the velocity of the materials increases with depth. It is not applicable to layered pavement systems where strong, high velocity layers occur at the top and grow progressively weaker with depth. How ever, Moore et al. (79) report that this procedure has been used to obtain compression wave velocities of pavement layers during construc tion. A method of using surface waves to structurally characterize pave ments is currently in the research stage at the University of Texas at Austin (80,81,82). The technique, called Spectral Analysis of Surface Waves (SASW), determines shear wave velocity at soil or pavement sites. The elastic shear and Young's moduli profiles are then calculated under 32 the assumption of homogeneous, isotropic, and elastic medium. The SASW method is essentially a seismic procedure. An iterative inversion process is used to interpret the shear wave velocity profiles (81). Laboratory procedures are available for the determination of the elastic properties of pavement and soil specimens using wave propagation techniques. However, the laboratory procedures require that samples of the pavement material be obtained for testing. Therefore, it may not be considered as a nondestructive technique. Two laboratory procedures that parallel the field vibratory procedures and which may be applicable to pavement design are the resonant column and the pulse methods (79). The most difficult aspect of the wave propagation techniques is that of interpretation and analysis of test results. The wave propaga tion method of testing relies on the ability to interpret the data obtained in the field so that the characteristics of the structure beneath the surface may be determined (79). Because of the inherent complexities involved, such techniques have not gained wide acceptance. 2.3.3 NDT Data-Interpretation Methods 2.3.3.1 General. Considerable emphasis has been placed upon determining the elastic properties of pavement layers using NDT data. Most of this work has been concentrated on the first three types of NDT procedures, those associated with deflection measurements. The fourth category, the wave propagation method, has not gained wide acceptance because of the relative sophistication required in the field operation and in the interpretation of test data. However, the interpretation of measured surface deflection basins has gained widespread popularity with the advent of NDT procedures. There is a general agreement among 33 pavement engineers that the measured surface deflection basins from NDT can provide valuable information for structural evaluation of a pave ment. Methods for the interpretation of NDT data can be placed into two categories: empirical or mechanistic methods. Empirical procedures directly relate NDT response parameters to the structural capacity of a pavement. Most of these methods (48,56) do not involve direct or indirect theoretical analysis. Instead, they are based upon the cor relation between the maximum deflection under a load (static NDT or wheel load) and pavement performance. In an attempt to improve the empirical procedures, other research ers have relied on the use of deflection basin parameters (90) or semi- empirical correlations (79) for pavement evaluation. Figure 2.7 shows an example of basin parameters and the criteria used to evaluate a pave ment. Table 2.1 lists some of the deflection basin parameters that have been developed for NDT data evaluation of pavements (120). Most of the basin parameters do not relate directly to the elastic parameters of the pavement section. Semi-empirical procedures usually involve correlation of modulus values to other known pavement parameters. For example, Heukelom and Foster (43) have developed a correlation between modulus E (in psi) from wave propagation techniques and the California Bearing Ratio (CBR) value. This correlation, though later refined by WES (79), is of the form E 1500 (CBR) Eqn. 2.3 34 DMD = Dynaflect Maximum Deflection (Numerical Value of Sensor No. 1) SCI = Surface Curvature Index (Numerical Difference of Sensor No. 1 and No. 2) BCI = Base Curvature Index (Numerical Difference of Sensor No. 4 and No. 5). a) Basin Parameters (b) DMD SCI BCI CONDITION OF PAVEMENT STRUCTURE GT 1.25 GT 0.48 GT 0.11 Pavement and Subgrade Weak LT 0.11 Subgrade Strong, Pavement Weak LT 0.48 GT 0.11 Subgrade Weak, Pavement Marginal LT 0.11 DMD High, Structure Ok LT 1.25 GT 0.48 GT 0.11 Structure Marginal, DMD Ok LT 0.11 Pavement Weak, DMD Ok LT 0.48 GT 0.11 Subgrade Weak, DMD Ok LT 0.11 Pavement and Subgrade Strong b) Criteria Figure 2.7 Empirical Interpretation of Dynaflect Deflection Basin (90) Table 2.1 Summary of Deflection Basin Parameters Parameter Definition3 NDT Device13 Dynaflect maximum deflection (DMD) DMD = d l d-d 1 2 d d 4 5 Dynaflect Surface curvature index (SCI) SCI = Dynaflect, Road Rater model 400 Base curvature index (BCI) BCI = Dynaflect Spreadability (SP) SP = ( Id. /56J x 100 Dynaflect i=l to 5 SP = ( Idi /4di) x i=l to 4 100 Road Rater model 2008 Bsin slope (SLOP) SLOP = d-d Dynaflect Sensor 5 deflection (W ) 5 W 5 = 1 !) d 5 Dynaflect Radius of curvature (R) R = r2/f2-dm[(Vdr) -1]} Benkelman beam Deflection ratio (Qr) Qr = r/dQ FWD, Benkelman beam Area, in inches (A) A = 6[ 1 + 2(d /d ) + 2 1 2(d /d ) 3 1 + (d /d )] Road Rater model 2008 4 1 Shape factors (F F ) 1 2 F l = (d d )/d 1 3 2 Road Rater model 2008 F 2 = (d d )/d 2 4 3 Tangent slope (TS) TS = (dm dxVx a d = deflection; subscripts 1,2,3,4,5 = sensor locations; o = center of load; r = radial distance; m = maximum deflection; x = distance of tangent point from the point of maximum deflection. b The NDT device for which the deflection parameter was originally defined. Source: Uddin et al. (120) 36 and is the most widely used correlation (133). Other correlations (79) have been made between E and plate bearing subgrade modulus, K. It should be recognized that the conditions of dynamic testing generally yield moduli in the linear elastic range. Conventional tests such as the CBR and plate bearing tests produce deformations that are not completely recoverable and, therefore, are partly in the plastic range. Thus, one would expect some variation in the correlation between E modulus and pavement parameters, such as K and CBR. Mechanistic analysis of NDT data is usually performed by one of the following: 1. Direct relationship between deflection parameters and the elastic moduli of the pavement layers. 2. Inverse application of a theoretical model by fitting a measured deflection basin to a deflection basin using an iterative procedure. 3. A combination of 1 and 2. The above mechanistic methods employ deflection data from either vibra tory or impulse loading equipment. While these devices are dynamic in nature, most of the mechanistic solutions are based on elasto-static (19,32,74) and visco-elasto-static (7) models. Recently, an elasto- dynamic model (54) has been used to interpret NDT data (66,67,105). However, the use of dynamic analyses for interpretation of NDT data can be considered to be in the research stage. Another significant obser vation is that almost all the mechanistic solutions available employ layered theory or simplified versions of it. The only exception to this is the use of a finite element model presented by Hoffman and Thompson (45). A review of the various solutions is presented below. 37 2.3.3.2 Direct Solutions. Presently, there are no direct analy tical solutions that can uniquely determine the elastic moduli for a multilayered pavement system using surface deflection measurements alone. The so-called direct solutions have been developed for only two- layer systems which usually involve graphical solutions, nomographs, or in most cases only provide estimates for the subgrade modulus. Scrivner et al. (102) presented an analytical technique for using pavement deflections to determine the elastic moduli of the pavement and subgrade assuming the structure is composed of two elastic layers. Based upon the same assumption, Swift (113) presented a simple graphical technique for determining the same two elastic moduli. Vaswani (124) used Dynaflect basin parameters to develop charts for the structural evaluation of the subgrade and its overlying layers for flexible pave ments in Virginia (see Table 2.1). The methods by Majidzadeh (64) and Sharpe et al. (107), among others, employ similar basin parameters from the Dynaflect or Road Rater to estimate the subgrade modulus and develop charts to assess the overlying layers. Jimenez (51) described a method for evaluating pavement-layer modular ratios from Dynaflect deflections. The pavements were considered to be three-layer systems, and the deflection data were used to estimate ratios of the elastic moduli of the adjacent layers. The ratios reduce the system from three values of elastic modulus to two values of modular ratio. The major limitation of this method is that the elastic modulus of the asphalt concrete layer must be known. Wiseman (129) and Wiseman et al. (131) have, respectively, applied the Hertz Theory of Plates and the Hogg Model to evaluate two-layered flexible pavements using surface deflection basins. The Hertz theory is 38 an application of the analytical solution of a vertically loaded elastic plate floating on a heavy fluid. The solution to this problem was presented by Hertz in 1884 and was first applied to concrete pavement analysis by Westergaard in 1926 (79). The Hogg model consists of an infinite plate on an elastic subgrade. The subgrade can be either of infinite extent or underlain by a perfectly rigid rough horizontal bottom at a finite depth. Analysis of this model was reported by A.H.A. Hogg in 1938 and 1944 (131). In both methods, the flexural rigidity of the composite pavement which will best fit a measured deflection basin is calculated. Lytton et al. (62) and Alam and Little (5) have developed another method based on elastic-layer theory for prediction of layer moduli from surface deflections. This method makes use of the explicit expression for deflection originally postulated by Vlasov and Leont'ev (126). The major drawback of this technique is the need to develop several con stants, five in all, for which no analytical or test method exists as yet. In applying this method, the authors (5,62) resorted to the use of regression analyses and computer iterative solutions. Cogill (28) presented a method which provides an estimate of the stiffness of the pavement-layer materials. The method essentially is a graphical presentation in which the deflections measured over a parti cular range of load spacing can be related to the stiffness of the pave ment material at a certain depth. The relationship is an approximate one and is expressed with the aid of Boussinesq's formula. All the methods presented above use deflection measurements obtained from vibratory loading equipments--Dynaflect and Road Rater. The only approach for the direct estimation of layer moduli from impulse 39 load-deflection response (such as an FWD deflection basin) is the concept of equivalent layer thickness (121,122) in which the layered pavement system is transformed into an equivalent Boussinesq (13) system. This concept, originally proposed by Odemark (87), is based on the assumption that the stresses, strains, and deflections below a given layer interface depend on the stiffness and thickness of the layers above that interface. Although this approach obtains an explicit solution for the subgrade modulus (121), it relies on estimates of the asphalt concrete layer modulus and also employs certain modular ratios to obtain the moduli of the various layers above the subgrade (25). The method of equivalent thicknesses (MET) has also been incorporated into some iterative computer programs which are discussed in the next section. Several investigators have obtained equations to directly determine the subgrade modulus from one or more sensor deflections. For example, Figure 2.8 shows the relationship between the subgrade modulus and the Dynaflect fifth sensor deflection as summarized by Way et al. (128). Keyser and Ruth (55) developed a prediction equation from five test road sections in the Province of Quebec, Canada, by using the BISAR elastic- layer program to match measured Dynaflect deflection basins. The equation is of the form -1.0006 E = 5.3966(D ) Eqn. 2.4 4 5 where E^ is subgrade modulus in psi, and D5 is Dynaflect fifth sensor deflection in inches. This equation had an R2 of 0.997 (55), and is similar to that of Ullidtz (see Figure 2.8). Godwin and Miley (41) have SUBGRADE MODULUS, Esg> psi 100,000 10,000 1,000 Figure DYNAFLECT DEFLECTION, D5, mils .8 Dynaflect Fifth Sensor Deflection-Subgrade Modulus Relationship (128) 41 developed correlations between the base, subbase and subgrade moduli and the second, third, and fourth Dynaflect sensor deflections, respec tively. However, the modulus values used in the correlation were the surface moduli from plate bearing tests which suffers from the problem of incorporating plastic and nonrecoverable deformations. An approach using regression equations to estimate layer moduli has been attempted by other investigators (83,120,132). This approach usually involves analysis of computer-simulated NDT data using a theo retical model (usually layered elastic theory). The various investi gators reported success in the case of the subgrade modulus. To obtain good correlations for the other layers (surface, base, subbase), certain assumptions had to be made, such as the base course modulus being greater than the modulus of the subgrade (83), or they had to resort to computer-iteration programs (83,120). 2.3.3.3 Back-Calculation Methods. The method of iteratively changing the layer moduli in a theoretical model to match the theoreti cal deflection basin to a measured basin is currently called back- calculation in the literature. Initial developments of this procedure utilized a trial-and-error approach (49,72) using the following steps: 1. Pavement-layer thicknesses, initial estimates of the pavement-layer moduli, and the loading and deflection measurement configuration are input into the model (usually a multilayer elastic computer program). 2. The computed deflections at the geophone positions are compared with those actually measured in the field. 3. The layer moduli used in the computer program are then adjusted to improve the fit between the predicted and actual deflection basins. 42 4. This process is repeated until the two deflection basins are vir tually the same. The process may have to be repeated several times before a reasonable fit is obtained. Because of the time consuming nature (49) of the trial-and-error method, many researchers have developed computer programs to perform the iteration. Table 2.2 lists some of the self-iterative computer pro grams. The major differences among the various programs are the differ ent models, algorithms and tolerance levels used in the iteration pro cess. A few of these will be discussed here. Anani (6) developed expressions for surface deflections in terms of the modulus values of a four-layer pavement. However, he could not obtain direct solutions to determine the moduli. Therefore he used an iterative procedure to obtain the moduli from Road Rater deflection basins. The computer programs reported by Tenison (114) and Mamlouk (66) followed the successive approximation method of Anani (6). In the overlay design program called OAF, Majidzadeh and lives (65) employed a deflection matching technique for determining the in situ layer stiff nesses. While using field data to substantiate the applicability of the procedure, they experienced difficulties and commented, . . the computed asphalt layer stiffness shows a large variation, and in a few cases the asphalt is stiffer than steel; nevertheless the values are reasonable in a great majority of the cases . . (65, p. 85) The BISDEF computer program (23) is an improvement over the CHEVDEF (22) to handle multiple loads and variable interface conditions. The number of layers with unknown modulus values cannot exceed the number of measured deflections. However, a maximum of four deflections are Table 2.2 Summary of Computer Programs for Evaluation of Flexible Pavement Moduli from NOT Devices Name Reference Number of Layers Theoretical Model Used For Analysis Applicable NOT Device * Anani (6) 4 Layer BISAR-E1astic Road Rater 400 ISSEM4 Sharma and Stubstad (106) 4 ELSYM5-E1astic Layer FWD CHEVDEF Bush (22) 4(a) Layer CHEVR0N-E1astic Road Rater 2008 OAF Majidzadeh and lives (65) 3 or 4 ELSYM5 Elastic Layer Dynaflect, Road Rater, or FWD ILLI-PAVE Hoffman and Thompson (45) 3 Finite Element Road Rater 2008, or FWD * Tenison (114) 3 Layer CHEVRON'S n (Elastic) Road Rater 2000 FPEDD1 Uddin et al. (118,120) 3 or 4 ELSYM5 Elastic Layer Dynaflect, FWD BISDEF Bush and Alexander (23) 4(a) BISAR Elastic Layer Vibrator, or FWD Dynaflect, Road Rater, WES ELMOD Ullidtz and Stubstad (123) 2, 3 or 4 MET-Boussinesq FWD IMD Husain and George (47) 3 or 4 CHEVRON Elastic Layer for FWD Dynaflect, but can be modified DYNAMIC Mamlouk (66) 4 Elasto-dynamic Road Rater 400 * not known or available (a) not to exceed number of deflections 44 targeted during the iteration process, which is also limited to a maximum of three loops. When applied to field measured deflections on an airfield pavement in Florida (23), BISDEF predicted unreasonably high values of the AC modulus for all the different NDT devices used in the study. Also, Bush and Alexander (23) conceded that the program,,provides the best results if the number of unknown layer moduli is three. The ISSEM4 computer program (106) incorporates the principles of the method of equivalent thicknesses (MET) into the ELSYM5 multilayered elastic program to determine the in situ stress-dependent elastic moduli. The parameters for the nonlinear stress-dependent relationships (see Section 2.4.3) are established from FWD tests performed at differ ent load levels. The iteration process is seeded with a set of E-values (106). The ELMOD program (123) also utilizes the MET principle and the iteration procedure. Both programs provide relatively good solutions if the asphalt concrete modulus is known. ILLI-PAVE (45), the only program which utilizes a finite element model, is specifically developed to handle Road Rater deflection data. However, Road Rater deflection basins must be converted to equivalent FWD deflection basins prior to being used in the program (45). Also, the nonlinear stress-dependent material models incorporated into the finite element method utilized relationships established from previous laboratory material characterization procedures. It is also surprising that the authors resulted to nomographs for specific applications of the back-calculation model (45). Most of the iteration programs listed above require a set of ini tial moduli--seed moduli--and therefore are user-dependent. Therefore computational times and cost can be prohibitive. Unique solutions 45 cannot be guaranteed since an infinite number of layer modulus combina tions can provide essentially the same deflection basins. Moreover, most of the iterative programs yield questionable base course and subbase moduli. In some programs, adjustment of the field data are required in order to improve the solution (6,47). 2.3.4 Other In Situ Methods Cogill (27) presented a method involving the use of an ultrasonic technique. The elastic modulus of the top layer can be accurately determined; however, the modulus values for the other layers are questionable. Kleyn et al. (58) and Khedr et al. (57) have developed different forms of a portable cone penetrometer to evaluate the stiff ness of pavement layers and subgrade soils. However, these devices do not provide direct modulus values but rather are based on correlations with CBR and plate bearing parameters. Similarly, the Clegg Impact tester, which was developed in Australia in the mid-1970s, relies on CBR correlation for pavement evaluation applications (40). The problems of the CBR and plate bearing tests have been discussed previously. Maree et al. (70) presented an approach to determine pavement-layer moduli based on a device developed to measure deflections at different depths within a pavement structure. The device, called the multi-depth deflectometer (MDD), is installed at various depths of an existing pave ment structure to measure the deflections from a heavy-vehicle simulator (HVS) test. Maree et al. (70) suggested that effective moduli for use in elastic-layer theory can be determined from correction factors esta blished from field measurements using the MDD at different times of the year and under different conditions. 46 Molenaar and Beuving (77) described a methodology in which the FWD and a dynamic cone penetrometer (DCP) were used to assess stress depen dent unbound pavement layers and the presence of soft interlayers. However, the procedure does not provide any direct modulus correlation but a graphical presentation of FWD surface modulus and DCP profiles. Geotechnical engineers have, for several years, used various forms of field tests to assess the engineering properties of soils for con struction purposes. Recent advances in exploration and interpretation methods have led to improvements in the determination of important soil parameters such as strength and deformation moduli. For example, the following in situ techniques (26,30,50) are suitable for the determina tion of soil stiffness: 1. Menard Pressuremeter (PMT) and Self-Boring Pressuremeter (SBP) tests. 2. Cone Penetration Test (CPT), including the mechanical, electronic, and piezo-cone penetrometers. 3. Marchetti Dilatometer Test (DMT). 4. Plate Loading Tests (PLT), including Screw Plate Tests (SPL). Some of these tests have the added advantage of providing detailed information on site stratification, identification, and classification of soil types. This is of great appeal since the variation of the subgrade soil properties with depth can be accounted for rather than assuming an average modulus value as conventionally used in multilayer analysis. Unfortunately, the application of the improved techniques to eval uate or design pavements has been very limited. As evident from the previous sections, the material characterization part of a rational 47 pavement design program, though very important, is often treated with considerable simplification and empiricism. Geotechnical engineers often feel that structural engineers have little or no interest in those parts of their work below the ground level. These feelings are cer tainly justified in the case of pavements (76). It is therefore not surprising that most of the in situ geotechnical applications to pave ments rely on correlations with empirical pavement parameters such as CBR to validate their proposed methods (40,57,58,77). The other known applications of geotechnical in situ testing methods to evaluate the stiffness of pavement structures are discussed below. Briaud and Shields (14,15) have described the development and procedure of a special pressuremeter test for pavement evaluation and design. The pavement pressuremeter consists of a probe, tubing and a control unit, and works on the same principle as the Menard pressure meter (30). They illustrated how the modulus values obtained from the test can be used directly in multilayer mechanistic analysis. In order to use empirical design charts, however, Briaud and Shields (15) also developed a correlation between the pressuremeter modulus and the bearing strength obtained from a Macleod plate test for two airport pavements in Canada. Borden et al. (12) have presented an experimental program in which the dilatometer test (68) was used to determine pavement subgrade sup port characteristics. A major part of the testing program consisted of conducting DMT and CBR tests in soil samples prepared in cylindrical molds and also in a special rectangular chamber. A limited field test was conducted on a compacted embankment constructed with one of the soils used in the laboratory investigation. Although they report good 48 correlations between the dilatometer modulus and CBR value, the use of the CBR test makes the study empirical, to say the least. 2.4 Factors Affecting Modulus of Pavement-Subgrade Materials 2.4.1 Introduction The response characteristics of flexible pavement materials is a complex function of many variables, which is far-fetched from the ideal materials assumed in classical mechanics. In general, the behavior of these materials is dependent upon many environmental and load vari ables. Specifically, the asphalt concrete response is primarily a function of temperature and rate of loading. Due to its viscoelastic nature (7,51), asphalt concrete materials become stiffer as the load rate increases and the temperature decreases. The granular base course and subgrade characteristics are dependent upon moisture content, dry density, stress level, stress states, stress path, soil fabric, stress history, and soil moisture tension (59,78,133). Several researchers have presented relationships of resilient modulus as a function of one or more variables, while keeping others fixed or completely ignored. Most of these relationships were developed from laboratory studies. A complete review of the relative effects of the various factors on pavement-soil response, or the relationship between modulus and other parameters measured in the laboratory can be found in References 31, 44, 59, 78, 94, and 133. It is not the intent of this discussion to review the various studies on this topic. The discussion below will concentrate on two variables that are believed to be very important in flexible pavement technology, especially when con sidering NDT and pavement evaluation. These factors are the temperature 49 of the asphalt concrete layer, and the stress dependency of base/subbase and subgrade materials. This does not mean that the effects of the other variables can be ignored or underestimated. For example, moisture content has a considerable effect on the modulus of flexible-pavement materials, especially for fine-grained subgrade soils (78). 2.4.2 Temperature Temperature has a very important influence on the modulus of asphalt-bound materials. The modulus of asphalt concrete decreases with an increase in pavement temperature (51,78,111,133). The temperature of the pavement also fluctuates with diurnal and seasonal temperature vari ations. In order to determine the variation of modulus with temperature for flexible-pavement materials, the mean pavement temperature should be established. Southgate and Deen (111) developed a method for estimating the temperature at any depth in a flexible pavement up to 12 inches. Figure 2.9 shows the graphical solution for the determination of the mean pavement temperature with depth from the known temperatures. This relationship has been recommended and in some cases incorporated into many flexible pavement design procedures (47,65,107). Though, the curves have been found to be reasonably accurate for other locations (111), it would be more desirable to make a direct determination of this temperature. 2.4.3 Stress Dependency Laboratory studies presented in the literature (31,44,78,94) sug gest that the moduli of granular base materials and subgrade soils are stress-dependent. The stiffness of the granular base has been found to be a function of the bulk stress or first stress invariant. A stress- stiffening model in which the modulus increases with the first stress TEMPERATURE AT DEPTH, F TEMPERATURE AT DEPTH,F 50 PAVEMENT TEMPERATURE + 5 DAY MEAN AIR TEMPERATURE a) Pavements More Than 2 in. Thick PAVEMENT TEMPERATURE + 5 DAY MEAN AIR TEMPERATURE b) Pavements Equal to or Less Than 2 in. Thick Figure 2.9 Temperature Prediction Graphs (111) 51 invariant is generally used to characterize granular base materials. The relationship is of the form K E = K^e 2 Eqn. 2.5 where E = granular base/subbase modulus, 0 = first stress invariant or bulk stress, and K K = material constants 1 2 The subgrade stiffness, on the otherhand, has been found to be a function of the deviator stress (stress difference). For fine-grained soils, resilient modulus decreases with increase in stress difference (78). The mathematical representation of the subgrade stiffness is of the form E Eqn. 2.6 where E = subgrade modulus a = stress difference, and A, B = material constants for the subgrade The constant B(slope) is less than zero for the stress-softening model, while for the stress-stiffening model, the slope is greater than zero. The stress-dependency approach of characterizing pavement materials is of great importance for high traffic loadings. Situations in which high traffic loadings occur are larger aircraft loadings in the case of airfield pavements, and when heavy wheel loads and/or single tire 52 configurations (which result in higher stresses) are applied to flexible highway pavements. For this reason, some of the NDT back-calculation procedures have accounted for the stress dependency effect by incorpo rating Equations 2.5 and 2.6 into their algorithms (45,65,106). How ever, the problem of determining the material constants, A, B, K and K still remains, especially when NDT deflection basins are used to 2 characterize the pavement. The most common approach is to use labora tory resilient moduli and regression analysis to determine these para meters (45,65,72). Thus, the material parameters will depend upon sample preparation procedures, disturbance, prestress-strain conditions, etc. Other researchers (93,106,121) have suggested determining the mate rial constants from FWD tests conducted at three or more load levels. However, it is not clear how viable this procedure is since the resul tant load-deflection response of a pavement is a combined effect of the behavior of the individual layers. The relative contribution of each layer is not clearly known. It is even more complex since the asphalt concrete layer is dependent on the temperature and age-hardening characteristics of the asphalt cement. Moreover, contrary to previous belief, Thompson (116) has found that the material parameters are not independent-of each other, especially for granular bases and subbases. Uddin et al. (118,119,120) have applied the concepts of equivalent linear analysis developed in soil dynamics and geotechnical earthquake engineering to evaluate the nonlinear moduli. They concluded that the in situ moduli derived from an FWD deflection basin (at 9000-lb. peak force) are the effective nonlinear moduli and need no further correc tion. However, an equivalent linear analysis has to be performed to 53 correct the in situ moduli calculated for nonlinear granular materials and subgrade soils from a Dynaflect deflection basin. These conclusions were based on stress analysis comparisons of a single-axle 18-kip design load, FWD (9000-lb. peak force) and Dynaflect loadings simulated in the ELSYM5 elastic-layer program. An algorithm to perform this equivalent linear correction has been incorporated into the FPPE0D1 self-iterative computer program (120). However, results reported by Nazarian et al. (81) tend to contradict the conclusions of Uddin et al. (120). Their study involving FWD tests at 5- and 15-kip loads indicated that non linear behavior occurs at higher FWD loads, and is more predominant in the base course layers than the subgrade. These results and those from other research work indicate there is disagreement as to what type of approach should be used when the effects of nonlinearity and stress dependency are to be considered. There are at least three schools of thought in this regard. The first group believes that the use of an equivalent effective modulus in an elastic- layer theory would provide reasonable response predictions. This approach would eliminate the expense, time and complexity associated with more rigorous methods such as finite element models (61). The research works of Maree et al. (70), Roque (96), and Roque and Ruth (97) on full-scale pavements tend to support this theory. The second school of thought recommends that the nonlinear stress dependent models (Equations 2.5 and 2.6) can be incorporated into an elastic-layer program to predict reasonable response parameters. How ever, the asphalt concrete layer is treated as linear elastic. This theory is supported by Moni smith et al. (78), among others, and has been used in iterative computer programs like OAF, ISSEM4, and IMD. 54 The third school of thought contends that layered elastic theory, when used with certain combinations of pavement moduli, predicts tensile stresses in granular base layers, even if gravity stresses are also considered (16,45,112). Instead of using a layered approach, this group prefers a finite element model in which the nonlinear responses of the granular and subgrade materials are accurately characterized. Again, the asphalt concrete layer is considered to be linear elastic. The ILLI-PAVE finite element back-calculation program (45) is a classic application of this theory. In the finite element approach discussed above, researchers have used, with limited success, various failure criteria and in some cases arbitrary procedures to overcome the problem of tensile stresses (16,112). For example, Brown and Pappin (16) used a finite element program called SENOL with a K-0 contour model and found it to be capable of determining surface deflections and asphalt tensile stresses but unable to determine the stress conditions within the granular layer. The asphalt layer was characterized as elastic with an equivalent linear modulus. They therefore concluded that the simplest approach for design calculations involves the use of a linear elastic-layered system pro vided adequate equivalent stiffnesses are used in the analysis. This conclusion is shared by other investigators (10,61,96,97) and is the philosophy behind the work presented in this dissertation. CHAPTER 3 EQUIPMENT AND FACILITIES Most of the methods available for determining the elastic moduli of flexible pavements have been outlined in Chapter 2. These include the use of nondestructive tests (NDT), laboratory methods and other in situ test methods. The limitations of these methods and the need for a more simple approach have also been highlighted. An approach which mechanis tically evaluates pavements with the use of NDT and/or in situ penetra tion tests is therefore developed in this study. This approach is developed to simplify the mechanistic analysis and design process, and to evaluate the effects of important variables involved in the determi nation of pavement layer moduli. The study consisted of the development of moduli prediction equations from NDT data, field testing and analyses of NDT and in situ penetration tests, and finally, comparison and eval uation of test data. Therefore, this chapter describes the equipment and facilities used in the study. The test equipment were either available at the Civil Engineering Department of the University of Florida or at the Bureau of Materials and Research, Florida Department of Transportation (FDOT). They are essentially standard testing devices. This research was concerned with their optimum use and application for a rational mechanistic design and evaluation of asphalt concrete pavements. 55 56 3.1 Description of Dynaflect Test System 3.1.1 Description of Equipment The Dynaflect, as previously mentioned, belongs to the dynamic steady-state force-deflection group of NDT equipment. It is an electro mechanical device for measuring the dynamic deflection of a pavement caused by oscillatory loading. The testing system (84,104,108) consists of a dynamic force generator mounted on a small two-wheel trailer, a control unit, a sensor assembly and a sensor (geophone) calibration unit. The Dynaflect can be towed by and operated from any conventional passenger carrying vehicle having a rigid trailer hitch and a 12-volt battery system. The oscillatory load is produced by a pair of counter weights rotating in opposing directions and phased in such a manner that each contributes to the vertical force of the other, but opposes the horizon tal force of the other, thereby canceling horizontal forces. The weight of the unbalanced masses varies sinusoidally from 2500 lbs. to 1500 lbs., thereby producing a cyclic force of 1000 lbs. peak-to-peak at a frequency of 8 Hz (see Figure 3.1). The cyclic force is alternately added to and subtracted from the 2000-lb. static weight of the trailer. The 1000-lb. cyclic force is transmitted to the pavement through a pair of polyurethane-coated steel wheels that are 4-in. wide and 16-in. in outside diameter. These rigid wheels are spaced 20-in. center to center (see Figure 3.2). The pavement response to the dynamically applied load is measured by five geophones located as shown in Figure 3.2. The first geophone measures the deflection at a point midway between the rigid wheels while the remaining four sensors measure the deflection occurring directly FORCE EXERTED ON PAVEMENT f = Driving Frequency = 8 Hz 1/f ] TIME Figure 3.1 Typical Dynamic Force Output Signal of Dynaflect (108) 58 Loading (b) Configuration of Load Wheels and Geophones. Figure 3.2 Configuration of Dynaflect Load Wheels and Geophones in Operating Position (108) 59 beneath their respective locations along the centerline of the trail er. However, the geophone configuration can be easily changed to a desired pattern. Each geophone is equipped with a suitable base to enable it to make proper contact with irregular surfaces (108). Data are displayed by a digital readout for each sensor on the control panel which is umbilically attached to the trailer and can be placed on the seat of the towing vehicle beside the operator/driver. All operations subsequent to calibration are performed from the control panel by the operator/driver without leaving the towing vehicle. 3.1.2 Calibration The Dynaflect unit is calibrated by placing the sensors on a cam- actuated platform inside the calibrator furnished with each unit (108). This platform provides a fixed 0.005-in. vertical motion at 8 cycles per second. The corresponding meter reading of 5 mils is set in the control unit by adjustment of an individual sensitivity control for each geo phone. Subsequent deflection measurements are thus comparisons against this standard deflection. 3.1.3 Testing Procedure The normal sequence of operation is to move the device to the test point and hydraulically lower the loading wheels and geophones to the pavement surface (84,108). A test is performed and the data of the 5 geophone deflection readings are recorded. At this point the operator has the option of raising both the sensors and the loading wheels or only the sensors. With the rigid wheels down and the pneumatic tires lifted, the trailer may be moved short distances from one measuring point to another at speeds up to 6 mph on the loading wheels (108). 60 When the rigid wheels are out of contact with the ground, the trailer is supported on pneumatic tires for travel at normal vehicle speeds. The sensors and loading wheels are raised and lowered by remote control to enable such moves to be made quickly without need for the operator/driver to leave the towing vehicle (84,104,108). 3.1.4 Limitations The general limitations of dynamic steady-state NDT devices have previously been described. In addition to those, the technical limi tations of the Dynaflect device include (109) peak-to-peak loading is limited to 1000 lbs., load cannot be varied, frequency of loading cannot be changed, the deflection directly under the load cannot be measured, and it is difficult to determine the contact area. 3.2 Description of the Falling Weight Deflectometer Testing System The Falling Weight Deflectometer (FWD) is a deflection testing device operating on the impulse loading principle. As described pre viously, there are various forms of the FWD, with the most widely used one in the United States being the Dynatest Model 8000 FWD system. This is the type used by the FD0T and in the study reported herein. There fore, this section describes the operating characteristics of the Dyna test FWD test system. Like the Dynaflect, the FWD is also trailer mounted and can be easily towed by most conventional passenger cars or vans. The Dynatest 8000 FWD test system consists essentially of three main components (34,110), namely 1. a Dynatest 8002 FWD, 61 2. a Dynatest 8600 System Processor, and 3. a Hewlett-Packard HP-85 Table Top Computer. 3.2.1 The 8002 FWD The Dynatest 8002 FWD consists of a large mass that is constrained to fall vertically under gravity onto a spring-loaded plate, 11.8 in. in diameter, resting on the pavement surface (see Figure 2.4). A load range of about 1500 to 24000 lbs. can be achieved by adjusting the num ber of weights or height of drop or both. The impulse or impact load is measured by using a strain-gauge-type load transducer (load cell). The impact load closely approximates a half-sine wave (see Figure 2.5), with a duration of 25-30 msec which closely approximates the effect of moving dual-wheels with loads up to 24000 lbs. (110). Seven seismic deflection transducers or geophones in movable brack ets along a 2.25 m raise/lower bar are used to measure the response of the pavement to the dynamically applied load. The geophones, which are 50 mm in diameter and 55 mm high, operate at a frequency range of 2 to 300 Hz (34). One of the geophones is placed at the center of the plate, with the remainder placed at radial distances from the center of the plate (see Figure 3.3). In its present form, the FD0T measures deflec tions at radial distances of 0, 7.87, 11.8, 19.7, 31.5, 47.2, and 63.0 in. from the plate center. These deflections are respectively called D,D,D,D,D,D, and D in this study. 12 3 4 5 6 7 3.2.2 The 8600 System Processor The Dynatest 8600 system processor is a microprocessor-based con trol and registration unit which is interfaced with the FWD as well as the HP-85 computer (34,110). The processor is housed in a 19-in. wide 62 Figure 3.3 Schematic of FWD Load-Geophone Configuration and Deflection Basin (34) 63 case which is compact, light weight, and controls the FWD operation. It also serves as a power supply unit for the HP-85 computer. The system processor performs scanning and conditioning of the 8 transducer signals (1 load + 7 deflections). It also monitors the status of the FWD unit to insure correct measurements. 3.2.3 The HP-85 Computer The Hewlett-Packard Model 85 computer is used for input of control and site/tests identification data as well as displaying, printing, storing (on magnetic tape), editing, sorting, and further processing of FWD test data (34,110). 3.2.4 Testing Procedure The automatic test sequence is identified and programmed from the HP-85 keyboard. This includes the input of site identification, height and number of drops per test point, pavement temperature, etc. When the operator enters a "START" command, the FWD loading plate and the bar carrying the deflection transducers will be lowered to the pavement surface, the weight will be dropped from the pre-programmed height(s), and the plate and bar will be raised again. An audible "BEEP" signal tells the operator that the sequence is complete, and that he/she may drive onto the next test point. A complete measuring sequence normally takes about one minute, exclusive of driving time between test points, for three or four drops of the falling weight (34,110). The measured set of data (1 load + 7 deflections) will be displayed on the HP-85 for direct visual inspection, and the data will be stored on the HP-85 magnetic tape cartridge, together with site identification information, etc. The display, printed results, and stored results can be in either metric or English units (34). 64 3.2.5 Advantages The primary advantages of the Dynatest FWD, like many other impulse deflection equipment, are that the created deflection basins closely match those created by a moving wheel load of similar magnitude (11,45, 110,123), and the ability to apply variable and heavier dynamic loads to assess stress sensitivity of pavement materials. The Dynatest FWD test system has the added advantage that the resulting deflection basin is constructed from seven deflection measurements compared to five and three deflections in the KUAB and Phoenix Falling Weight Deflectometers, respectively. 3.3 BISAR Computer Program The analyses and evaluation of NDT deflection data in this study involved the use of BISAR, an elastic multilayered computer program. BISAR is an acronym for _Bitumen structures Analysis in _Roads. The program, developed by Koninklijke/Shell Laboratorium, Amsterdam, Holland, is a general purpose program for computing stresses, strains and displacements in elastic multilayered systems subjected to one or more uniform loads, acting uniformly over circular surface areas (32). The surface loads can be combinations of a vertical normal stress and unidirectional tangential stress. The use of BISAR to compute the state of stress or strain in a pavement requires the following assumptions (32): 1. Each layer of pavement acts as a horizontally continuous, isotropic, homogeneous, linearly elastic medium. 2. Each layer has finite thickness except for the lower layer, and all are infinite in the horizontal direction. 65 3. The surface loading can be represented by uniformly distributed ver tical stresses over a circular area. 4. The interface conditions between layers can vary from perfectly smooth (zero bond) to perfectly rough (complete bonding) conditions. 5. Inertial forces are negligible. 6. The stress solutions are characterized by two material properties, Poisson's ratio and Young's modulus for each pavement layer. BISAR was used over other layered-theory programs because of its availability, testedand proven--reliability and accuracy (72,91,96), and, also, its ability to handle variable layer interface conditions. For example, McCullough and Taute (72) found that the ELSY.M5 program (3) which is based on the CHEVRON program (74) predicts unrealistic deflec tions in the vicinity of the load. They therefore recommended the use of BISAR in computing fitted deflection basins, especially if the deflection measurements are made near the loading point. Also, Ruth et al. (98) reported correspondence with Mr. Gale Ahlborn, who developed the ELSYM5 program, that the program is unreliable for certain unpre dictable combinations of material properties. 3.4 Description of Cone Penetration Test Equipment The cone penetration test equipment consisted of a truck-mounted hydraulic penetration system, electronic cone penetrometers (95) and an automated data acquisition system. Detailed descriptions of the truck and its features have been presented by Davidson and Bloomquist (30). The hydraulic system serves two functions (29): leveling the truck and penetrating the cone. The leveling system consists of four 66 independently controlled jacks. The front two jacks are connected to a 2 ft. x 7 ft. reaction plate; the back two to separate 15-in. circular pads. The vehicle is lifted off the ground and leveling assured by means of a spirit level. The penetrating system consists of a 20-ton ram assembly located in the truck to achieve maximum thrust from the reaction mass of the vehicle. Two double-acting hydraulic cylinders provide a useable vertical stroke of 1.22 m. Prior to testing, the rams are used to raise the telescoping roof unit. When locked in the raised position, the unit allows full travel of the rams (29,30). The cone penetrometers are of the subtraction type configuration, with tip and friction strain gauges mounted on the central shaft (29,95). Cone bearing is sensed by compression in the first load cell, while the sum of cone plus friction is sensed in the rear load cell. The friction value is then obtained by subtraction, which is done electronically (29). The cones used also measure pore water pressure and inclination. A cable, threaded through the 1-meter long push rods, transmits the field recording signals to the data acquisition system. The University of Florida currently has three electric cones, with rated capacities of 5, 10 and 15 metric tons. Each measures tip resistance, local friction, pore pressure, and inclination. The 5- and 10-ton cones are of standard configuration with 10-cm tip areas and 150- cm friction sleeves. The larger 15-ton cone has the capability of testing in much stiffer soil materials. All three cones contain precision optical inclinometers which output the angular deviation of the cone from the vertical during penetration (30). 67 The electronic data acquisition system is capable of printing and plotting penetration data directly on the job site. It consists of a microprocessor with 128 k magnetic bubble memory, an operator's console with keypad, an Okidata microline 82A printer and an HP 7470A graphics plotter. The computer is programmed with preset limits defined to protect the probe from overloading. If a limit is exceeded, the computer automatically stops the test and displays the cause of the abort (29,30). The electronic cone penetration testing equipment has several advantages, such as a rapid procedure, continuous recording, high accuracy and repeatability, automatic data logging, reduction, and plotting. The CPT provides detailed information on site stratification, identification, and classification of soil types. Results have also been correlated with several basic soil parameters, including different deformation moduli. For example, Schmertmann's method (101) of computing settlements in sands requires the in situ variation of Young's modulus. This is obtained from the CPT cone bearing resistance. 3.5 Marchetti Dilatometer Test Equipment The Marchetti Dilatometer test (DMT) is a form of penetration test and is fully described in References 17, 29, 68 and 69. Basically, the test consists of pushing into the ground a flat steel blade which has a flush-mounted thin circular steel membrane on one face. At the desired depth intervals (usually every 20 cms) penetration is stopped, and measurements are taken of the gas pressure necessary to initiate deflection and to deflect the center of the membrane 1.1 mm into the 68 soil. These two readings serve as a basis for predicting several important geotechnical parameters, using experimentally and semi- empirically derived correlations (17,50,68). The DMT sounding provides indications of soil type, preconsolidation stress, lateral stress ratio at rest (KQ), Young's modulus (E), constrained modulus (M), shear strength in clays and angle of shearing resistance in sands. The major components of the dilatometer test equipment are the dilatometer blade, the gas-electric connecting cable, a gas-pressure source, and the read-out (control) unit. Figure 3.4 shows a schematic diagram of this equipment. In addition there is a calibration unit, adaptors, electric ground cable and a tool kit containing special tools and replacement parts. Detailed descriptions and functions of the various components are presented by Bullock (17) and Marchetti and Crapps (69). The dilatometer blade, as shown in Figure 3.4, consists of a stain less steel blade, 94 mm wide and 14 mm thick, bevelled at the bottom edge to provide an approximate 16-degree cutting edge. A 60 mm stain less steel circular membrane is centered on and flush with one side of the blade. The control unit, housed in an aluminum carrying case, contains various indicators, a pressure gauge and the controls for running the test. The control unit gauge used in the current study had a range of 0-40 bars. Higher and lower range units are also available. This gauge provides the gas pressure readings for the dilatometer test. The dilatometer blade is advanced into the ground using standard field equipment. The blade can be pushed or driven by one of the following methods (29): 69 To Pressure Figure 3.4 Schematic of Marchetti Dilatometer Test Equipment (69) 70 1. Using a Dutch Cone Penetrometer rig. This method is believed to yield the highest productivity, up to 250 or more tests per day. 2. Using the hydraulic capability of a drill rig. 3. Using the SPT rig hammer or similar lighter equipment. 4. With barge-mounted equipment or by wireline methods for underwater testing. 3.6 Plate Bearing Test The plate bearing test conceptually belongs to the static force- deflection group of NDT procedures (79). However, it can also be con sidered as a destructive field test since the testing requires the construction and subsequent repair of a trench or test pit. The plate bearing test consisted of the repetitive-static type of load test out lined in ASTM Test Procedure D 1195-64 (8). The main objective in this test is to measure the deformation characteristics of flexible pavements under repeated loads applied to the pavement through rigid, circular plates. Burmister's two-layer theory (18,19,20) is generally used to interpret plate load testing results (133). The test equipment used by the Florida Department of Transportation consists of a 12-inch diameter steel plate, loading system, deflection gauges and supports (41). A trailer loaded with a huge rubber container filled with water is used as a reaction. A hydraulic jack assembly is used to apply and release the load in increments. A detailed descrip tion of the repetitive-static plate load test is provided in ASTM test standards (8, pp. 258-260). CHAPTER 4 SIMULATION AND ANALYSES OF NDT DEFLECTION DATA 4.1 BISAR Simulation Study 4.1.1 General The Dynaflect and FWD loading-geophone patterns were simulated in the BISAR elastic-layer computer program to predict surface deflection data for four-layer pavement systems. A flexible pavement structure was modeled as a four-layer system with parameters shown in Figure 4.1. The selection of layer thicknesses and moduli was based on typical ranges in parameters representative of Florida's flexible pavement systems. In general, the limerock base and stabilized subgrade thick nesses were fixed at 8 in. and 12 in., respectively. Table 4.1 lists the range of layer parameters used in the theoretical analysis. The subgrade was generally characterized as semi-infinite in thickness with an average or composite modulus of elasticity. However, the effect of bedrock at shallow depth was also assessed by varying depth to bedrock in a five-layer system. Poisson's ratio was fixed at 0.35 for all the pavement layers since it has negligible effect on computed deflections. In using the layered theory to generate and analyze NDT deflection data certain assumptions had to be made. The following assumptions were made with the use of the BISAR program: 1. Pavement materials are homogeneous, isotropic, and linearly elastic. Therefore, the principle of superposition is valid for calculating response due to more than one load. 71 72 IDJCP ¡ i "i*1 i i ! ' E2 ^2 } ¡ i i h2 r 1 i 1 1 E3 ^3 ' 1 1 ' i H3 f j i i ^4 M4 ! ! 1 l 1 1 i H4 = OO r I Figure 4.1 Four-Layer Flexible Pavement System Model 73 Table 4.1 Range of Pavement Layer Properties Layer Number Layer Type Layer Thickness (in.) Poisson's Ratio Layer Modulus (ksi) 1 Asphalt Concrete 1.0 10.0 0.35 75 1,200 2 Limerock Base 8.0 0.35 10 170 3 Stabilized Subgrade (Subbase) 12.0 0.35 6 75 4 Subgrade (Embankment) Semi-infinite 0.35 0.35 200 74 2. Pavement layers are continuously in contact at the interfaces with shearing resistance fully mobilized between them, so that the four layers act together as an elastic medium of composite nature with full continuity of stresses and displacements. 3. The Dynaflect and FWD dynamic loads are modeled as static circular loads. Thus, the peak-to-peak dynamic force of the Dynaflect is modeled as two pseudo-static loads of 500 lbs. each uniformly distributed on circular areas. The peak dynamic force of the FWD is assumed to be equal to a pseudo-static load uniformly distributed on a circular area representing the FWD loading plate. 4. Thickness and Poisson's ratio of each layer are assumed to be known. 4.1.2 Dynaflect Sensor Spacing In order to determine the optimum locations of the five Dynaflect sensors, additional ones were included in the BISAR simulation study. These sensors were placed at intermediate positions near the loaded wheel and first two (standard) sensors, with hope of detecting the primary response of the upper pavement layers (surface and base course). Figure 4.2 illustrates the loading and modified geophone array. The Dynaflect was modeled in the BISAR program using two circular- loaded areas, with deflection measurement positions as shown in Figure 4.2. Each load is 500 lbs. in weight, and the contact area used in this study was 64 in.2, resulting in an equivalent radius of 4.5 in. 4.1.3 FWD Sensor Spacing The conventional sensor spacing used by the FDOT and four additional sensor locations were utilized in the analytical study. Sensors were placed at radial distances of 0, 7.87, 11.8, 16.0, 19.7, y Eg, and E^. The resulting power law relationships provided excellent prediction reliability with R2 values greater than 0.95. However, efforts to achieve a generalized E1 prediction equation with Dx as the main independent variable was complicated by the inter action of thickness and layer moduli values. Therefore, the difference in deflections between D1 and D2 through D5 were analyzed to determine if any of these values could be used to characterize E^ A multiple linear regression analysis (39) was used to obtain three equations for different ranges of t1 values. These E prediction equations are presented below and hold for deflections obtained with a 9-kip FWD load. Case 1. For 1.5 < t < 8.0 in., l log (E ) = 1.87689 0.41689(t ) 23.8735 log D D ) 1 l 12 + 43.582 log (D D ) 29.7179 log (D^ D ) - 8.80 log (D D ) (N = 400 and R2 = 0.932) Eqn. 4.18 Ill Case 2. For 3.0 < t < 8.0 in., l log (Ei) 1.4506 19.6499 log (D D ) + 32.5256 log (D D ) 12 13 - 18.6215 log (D D ) 4.78148 log (D D ) 14 15 Eqn. 4.19 (N = 320 and R2 = 0.979) Case 3. For 4.5 < t < 8.0 in., l log (E ) = 1.79194 10.8459 log (D D ) + 13.6157 log (D D ) - 3.65434 log (D D ) 1 4 Eqn. 4.20 (N = 240 and R2 = 0.993) The above equations hold for their respective range in tx values and the following range in moduli: 75.0 < E < 1200.0 ksi, 42.5 < E < 85.0 ksi, l 2 30.0 < E < 60.0 ksi, and 5.0 < E < 40.0 ksi. 3 4 The accuracy and reliability of these equations will be discussed later using both theoretical and field FWD deflection measurements. 4.3.3.2 Prediction Equations for E2. The sensitivity analysis presented in Section 4.2 suggested that it would be difficult to develop E2 prediction equations from FWD deflections. This was due to the relative lack of sensitivity of E on the theoretical FWD deflection 112 basins. Multiple regression analyses similar to those for Ex prediction equations were performed to develop equations suitable for the predic tion of E2. The results of these analyses indicated the following two equations provided the best overall accuracy for the range in variables used in the study. Case 1. For 150.0 < E < 300.0 ksi, 1.5 < t < 6.0 in., 1 l 42.5 < E < 170.0 ksi, 30.0 < E < 60.0 ksi, 2 3 and 10.0 < E < 40.0 ksi, 4 log (El 2 2.9271 0.109 t + 0.5104 log (t ) 0.3997 log (D ) + 4.213 log (D D ) 17.149 log (D D ) 12 14 + 12.295 log (D D ) (N = 240, and R2 = 0.962) Eqn. 4.21 Case 2. For 1.5 < t < 8.0 in., 5.0 < E < 40.0 ksi, and others as 1 4 listed for Equation 4.21, log (E ) = 3.06546 0.08134 t 0.1256 D + 0.2793 D 0.19322 D 2 1 1 2 5 + 0.2998 log t + 3.5381 log (D ) + 2.1045 log (D ) 2.4614 log (D ) 5 8 + 6.76643 log (D D ) 11.0912 log (D D ) 13 14 Eqn. 4.22 (N = 400, and R2 0.953) 113 The 10-variable regression equation presented above has some of the variables in Equation 4.21. The log (D D ) and log (D D ) terms 14 12 were found to make the most significant contribution to the R2 value of 0.953 (39). It must be noted that D0 is in Equation 4.22. This sensor deflection measurement is currently not made with the conventional sensor array utilized by the FOOT (see Section 3.2.1). 4.3.3.3 Prediction Equations for E?. The modulus of the sta bilized subgrade layer, E3, does not contribute any significant change on FWD deflection basins. As in the case of the Dynaflect, this layer was found to be difficult to develop moduli prediction equations. From the sensitivity analysis, the maximum percent change in deflections occurred at FWD deflections D2 and D3 when the original E3 value was doubled or halved (Tables 4.2 and 4.4). Therefore initial analyses involved the examination of the relationships between Eg and D2 or D3 using log-log plots. Simple power law equations with R2 values greater than 0.998 were generally obtained for various levels of Ex, E2, E^ and t These parameters were found to have considerable influence on the intercepts (Kx) and slopes (K2) of the power law relationships. Because of the complex interactions involved, it was difficult to combine some of the power law equations. Multiple linear regression analysis was performed on a subset of the theoretical deflections. An 8-variable prediction equation was obtained from the analysis. This is shown in Case 1. Case 1. For 150.0 < E < 300.0 ksi, 1.5 < t < 6.0 in., 1 l 42.5 < E < 170.0 ksi, 30.0 < E < 75.0 ksi, 2 3 and 10.0 < E < 40.0 ksi, 4 114 log (E3) 0.587 0.037 ti 10.19 + 8.01 log^) + 2.226 log(Dg) - 5.119 log (D D ) + 17.255 log (D D ) 13 15 - 6.101 log (D D ) 7.051 log D D ) 2 5 4 7 (N = 192, and R2 = 0.958) Eqn. 4.23 The database used to develop Equation 4.23 was then expanded to include E3 = 15 ksi, E4 = 5 ksi and tx = 8.0 in. combinations. Subsequent regression analysis resulted in a 5-variable prediction equation listed under Case 2. Case 2. For 150.0 < E < 300.0 ksi, 1.5 < t < 8.0 in., 1 i 42.5 < E < 85.0 ksi, 15.0 < E < 75.0 ksi, 2 3 and 5.0 < E < 40.0 ksi, 4 log (E ) = 3.8646 0.27061 log (t ) + 1.1212 log (D ) 3 16 - 1.849 log (D D ) + 12.009 log (D D ) 2 3 2 4 - 12.3637 log (D D ) Eqn. 4.24 2 5 (N = 400, and R2 = 0.935) 4.3.3.4 Prediction Equations for E,t. The subgrade modulus, E , was found from the sensitivity analysis to contribute significantly to the NDT deflections compared to the moduli of the upper layers. Changes in E4 affected the deflections to the greatest degree. Using the 9-kip 115 FWD deflections, the percent change in deflections due to changes in E4 increased from Dx to Dg. However, the rate of increase seemed to level off from Dc to D. (see Tables 4.2 and 4.4). These are the farthest O O sensor deflections used in the FWD theoretical study. Figures 4.21 and 4.22 show, for example, the relationships between E, and D., D_, or D for fixed levels of E,, E, E, and t,. The Hb/o 1231 subgrade modulus, E4, ranges from 5 to 100 ksi. Regression equations and R2 values for each power equation are indicated on the plots. Similar relationships with a high degree of correlation were obtained for pavements with tx values ranging from 1.5 to 10 in. Based on the unique relationships obtained for E4 and the last three FWD sensor deflections, the database was combined and also expanded to cover a large range of parameters listed in Table 4.1. The following power law equations were obtained by regressing E4 against Dg, or D?, or Dg. General Case: For 1.5 < t < 8.0 in., 75.0 < E < 1200.0 ksi, 1 i 42.5 < E < 85.0 ksi, 30.0 < E < 60.0 ksi, 2 3 and 5.0 < E <40.0 ksi, 4 54.6122 (D ) 1.03065 E Eqn. 4.25 6 (N = 400, and R2 = 0.9974) 39.9899 (D ) 7 0.98912 E (N = 400 and R2 = 0.9992) Eqn. 4.26 SUBGRADE MODULUS, E4 IN ksi 116 SENSOR DEFLECTION, D6 D7 D8 (mils) Figure 4.21 Relationship Between E and FWD Deflections for Fixed E1> E2, and E3 Values with tx = 3.0 in. SUBGRADE MODULUS, E4, IN ksi 117 SENSOR DEFLECTION, D6 D? D8 (mils) Figure 4.22 Relationship Between E4 and FWD Deflections for Fixed Ej, E2, and Eg Values with tx = 6.0 in. 118 , 0.97871 E = 34.8891 (D ) Eqn. 4.27 4 8 (N = 400 and R2 = 0.9996) In Equations 4.25 through 4.27, like the previous equations, modulus is in ksi, and deflections are in mils. Again, Dg and D? are deflections from sensors located at radial distances of 47.2 and 63.0 in., respec tively, in the conventional geophone spacings utilized by the FD0T. However, Dg is an additional sensor located at a radial distance of 72.0 in. which was included in this study. The FD0T does not have sensor 8 measurement (Dg) in their current sensor array system. Additional multiple linear regression analyses (39) were performed to see if there were any interactions among Dg, D?, and Dg which could provide an optimum relationship for the prediction of E^. The following two logarithmic equations were obtained: log (E ) = 1.51999 + 0.622145 log (D ) 1.58542 log (D ) Eqn. 4.28 4 6 7 (N = 400 and R2 = 0.9995) log (E ) = 1.48914 + 0.893689 log (D ) 1.86276 log (D ) (N = 400 and R2 = 0.9997) Eqn. 4.29 An equation combining all three independent variables Dg, D?, and Dq was not found from the multiple linear regression analysis. The applicable range of parameters (layer moduli and thicknesses) for Equations 4.25 through 4.29 are presented above. However, due to the unique relationship between E4 and the FWD sensor deflections, these 119 equations could be applied to an expanded range of parameters without introducing much error. The prediction accuracy of these equations and others are discussed in the next section. 4.4 Accuracy and Reliability of NDT Prediction Equations The previous section presented several layer moduli prediction equations for both the Dynaflect and FWD testing systems. The equations are theoretical in the sense that they were developed from theoreti cal ly-derived deflections (using the BISAR computer program), layer thicknesses and moduli. The prediction accuracy of these equations are assessed in this section. The various equations were used to predict and evaluate prediction errors. This was achieved by relating predicted moduli values to the true or actual values. High prediction errors were deleted from the data set and the remaining values were correlated to the actual values of moduli originally selected for analysis. In general, prediction errors of the order of 10 percent were considered to be compatible with the variabilities commonly noted in field deflection-basin measurements. 4.4.1 Prediction Accuracy of Dynaflect Equations 4.4.1.1 Asphalt Concrete Modulus, Er The complexity of devel oping a generalized equation to predict Ex for varying t1 and from D -D^ resulted in the development of three equations to cover the dif ferent ranges of E2 and tx (Equations 4.1 through 4.7). The accuracy of these equations is discussed below. Case 1: 10.0 < E < 30.0 ksi; and 3.0 < t < 6.0 in. 2 1 120 Equations 4.1 through 4.3 are applicable in this range. Therefore, these equations were used to compute Ex values for asphalt concrete thicknesses of 3.0, 4.5, and 6.0 in. Predictions were generally very good and within +10 percent of the actual Ej value when the true value of E2 was used. In general, the majority of the predicted E values were within +5 percent, with the maximum error being +22.5 percent. Pavements with Ex predictions above +10 percent are listed in Table 4.5. It can be seen from the table that these were very few considering the size of the data set analyzed. Correlation between predicted and actual E: values resulted in the following: Ej (Predicted) = 9.988 + 0.933E1 (Actual) Eqn. 4.30 (N = 58, R2 = 0.992) Attempts to predict outside of the designated thickness range resulted in errors up to 70 percent. Thus, it is imperative that the E prediction equations for Case 1 be used for the specified range. Case 2: 32.0 < E < 85.0 ksi; and 2.0 < t < 6.0 in. 2 l E: is predicted from Equations 4.1, 4.4, and 4.5. Comparisons between predicted and actual E1 values indicated that errors up to 90 percent could be obtained with the use of these equations. The higher errors occurred in pavements with extreme values of E^ (0.35 and 200 ksi). When these pavements were deleted, predictive errors were generally within the range of +20 percent, with a few cases going as high as +30 percent. 121 Table 4.5 Pavements with Dynaflect Ex Predictions Having More Than 10 Percent Error (Case 1 Equations 4.1-4.7) No. Layer Moduli (ksi) (in.) Predicted percent Difference (ksi) 300 10 15 10 3.0 261.6 -12.8 1000 10 6 10 3.0 1128.9 12.9 1000 10 6 50 3.0 1128.9 12.9 1000 30 15 10 3.0 1124.8 12.5 1000 10 15 10 4.5 1224.8 22.5 1000 30 15 10 4.5 1144.3 14.4 100 40 15 10 4.5 87.9 -12.1 100 10 6 0.35 6.0 114.6 14.6 1000 30 15 10 6.0 1123.8 12.4 9 122 Ex (Predicted) = 75.612 + 0.848E1 (Actual) Eqn. 4.31 (N = 97, R2 = 0.848) Deleting the cases with E^ equal to 0.35 and 200 ksi resulted in Ex (Predicted) = 28.707 + 0.989E1 (Actual) Eqn. 4.32 (N = 90, R2 = 0.934) The improvement in R2 value suggests that the Ex prediction equa tions for Case 2 should be used with caution when E, values are extremely low or high. Case 3: 10.0 < E < 85.0 ksi; and 7.0 < t < 10.0 in. 2 l For this case, Equations 4.1, 4.6, and 4.7 were derived to predict E . As mentioned previously, these equations appear to be simple compared with those for Cases 1 and 2. The relatively simple Ex prediction equations for Case 3 were developed using data for tx = 8.0 in. only, but it was found to be applicable for thicknesses between 7 and 10 in. This also suggests that for thicker pavements, the effect of tx on Ej, E2, and becomes negligible, as shown in Figures 4.17 and 4.18. The percent difference between actual and predicted Ex values for Case 3 were within +6 percent. Only three pavements exceeded this, having less than +10 percent error. When the predicted and true moduli values were regressed, the following equation was obtained. E1 (Predicted) = 2.896 + 0.991E1 (Actual) Eqn. 4.33 (N = 22, R2 = 0.998) 123 4.4.1.2 Base Course Modulus, E2, for Thin Pavements. For pave ments with very thin asphalt concrete layers, tx < 2.5 in., Equations 4.8 through 4.10 can be used to predict E2 with an estimate of E . Analysis of predicted E2 values indicated that errors were generally within the order of 10 percent for tx values of 1.0, 2.0, and 2.5 in. A few cases (8 out of 66) had errors up to +20 percent. These are listed in Table 4.6. Correlation between predicted and actual E2 values yielded the following equation: E2 (Predicted) = 2.3745 + 0.962E2 (Actual) Eqn. 4.34 (N = 66, R2 = 0.982) An attempt was made to extrapolate the equations to predict pavements with 3 inches or more of asphalt concrete layer. Errors as high as 40 percent were obtained, thus emphasizing the need to apply the equations to the stipulated range. 4.4.1.3 Stabilized Subgrade Modulus, Eg. The stabilized subgrade layer was initially found to be the most difficult layer for developing a rational prediction equation. Equations 4.11 through 4.13 which were developed for Case 1 with fixed tx and E1 values (3.0 in. and 100.0 ksi, respectively) had 24 out of 88 cases with predictive errors exceeding 15 percent. When the equations were used to predict pavements with Ex value of 1000.0 ksi, errors as high as 75 percent were obtained. Equation 4.14 (for Case 2), which was developed from a multilinear regression analysis, applies to pavements with AC thicknesses ranging 124 Table 4.6 Pavements with Dynaflect Predictions Having More Than 10 Percent Error (Case 4--Equations 4.8-4.10) No. Layer Modul i (ksi) (in.) Predicted e2 (ksi) Percent Ei E2 E3 E4 Difference 1 100 85 35 0.35 1.0 94.9 11.6 2 1000 10 35 0.35 1.0 11.3 13.0 3 100 85 15 10 2.0 75.5 -11.2 4 700 30 15 10 2.0 25.4 -15.3 5 700 85 15 10 2.0 96.0 12.9 6 1000 30 15 10 2.0 25.3 -15.7 7 1000 35 15 10 2.0 28.9 -17.4 8 1000 40 15 10 2.0 35.4 -11.5 125 from 3.0 to 6.0 in. This equation had an R2 of 0.933 for 134 number of cases. Predictions were generally within 10 percent of actual Eg values. Only 22 of the 134 total observations had more than 20 percent predictive error. It must also be noted that the use of this equation requires knowledge of the other layer moduli; namely E2 and E4. If any of these is off, then the E3 value predicted from Equation 4.14 would probably be in error. Thus, the reliability of the E3 prediction is dependent on the accurate estimates of the other layer moduli. Equation 4.15, which predicts E3 from D4-D?, is a relatively sim plified equation. Table 4.7 shows the high degree of accuracy of this equation to predict E Correlation between predicted and actual E values resulted in an R2 of 0.991. Extrapolation of this equation to predict outside the stipulated range resulted in errors as high as +60 percent. However, it will be shown later that this equation format, using field measured Oynaflect deflections, is applicable to a wider range of variables than those listed under Case 3. 4.4.1.4 Subgrade Modulus, E Equation 4.16, derived to predict the subgrade modulus, holds for a wide range of E4 (0.35 to 200.0 ksi). This equation has an R2 of 0.984 for 266 number of cases. Because of the wide range of E4, the equation tends to underpredict slightly for intermediate E4 values. Also, predictive errors greater than +60 percent were found to be typical for the extreme values of E4 (0.35 and 200.0 ksi). Therefore, those data were deleted and the remaining data set regressed to obtain Equation 4.17 with an R2 of 0.992 and N equal to 193. Equation 4.17 holds for E4 values between 10.0 and 50.0 ksi. Only 4 out of 193 E4 predictions fell above +15 percent. 126 Table 4.7 Comparison of Actual and Predicted E Values for Varying t2 (Case 3Equation 4.15) No. Layer Moduli (ksi) E1 E2 E 3 E*t *1 (in.) Predicted E3 (ksi) Percent Difference 1 150 38 18 14 1.0 17.2 -4.4 2 500 38 18 14 1.0 18.0 0 3 150 55 30 22 1.0 28.8 -4.0 4 500 55 30 22 1.0 30.0 0 5 150 38 18 14 2.0 17.9 -0.6 6 500 38 18 14 2.0 . 17.7 -1.7 7 150 55 30 22 2.0 30.1 0.3 8 500 55 30 22 2.0 29.8 -0.7 9 150 38 18 14 3.0 13.6 3.3 10 500 38 18 14 3.0 18.8 4.4 11 150 55 30 22 3.0 30.6 2.0 12 500 55 30 22 3.0 30.4 1.3 127 It was shown in Figure 4.20 that a simplified equation originally developed from field measured Dynaflect data could be used to predict E4 values varying from 10.0 to 100.0 ksi. The simplified equation = 5.4 (D T1-0 Eqn. 4.35 was used to predict all the data set originally used to develop Equation 4.16. The R2 value obtained from linear regression of predicted and actual E values was 0.830. However, when the extreme E values (0.35 and 200.0 ksi) were deleted, the R2 increased to 0.982. Thus, within the range of 10.0 to 100.0 ksi of subgrade modulus, Equation 4.35 is considered to be simple and accurate enough to predict E4. 4.4.2 Prediction Accuracy of FWD Equations 4.4.2.1 Asphalt Concrete Modulus, E1: Three equations were devel oped to predict Ex for different ranges of asphalt concrete thickness, tj. Equation 4.18 is valid for t: values varying from 1.5 to 8.0 in. The prediction accuracy of this equation is summarized in Table 4.8. In this table, the number of cases with percent predictive errors falling within certain limits are listed for varying tx values. The table illustrates that higher errors occur at tx values of 1.5 and 3.0 in. As tx increases, the percent error reduces substantially with t1 equal to 6.0 in. having most cases with less than 20 percent prediction error. Because of the high errors obtained with tx values of 1.5 in. in Equation 4.18, these values were deleted from the data set and the remaining data were analyzed to obtain Equation 4.19. This equation thus holds for tx values from 3.0 to 8.0 in., and had an R2 of 0.979 for 320 number of cases. The prediction accuracy of Equation 4.19 is also 128 Table 4.8 Prediction Accuracy of Equation 4.18--Error Distribution as a Function of tx Number of Cases with Percent Error Within (in.) > 60 50-60 40-50 30-40 20-30 15-20 < 15 1.5 2 9 12 18 10 5 24 3.0 3 9 9 7 19 10 23 4.5 0 0 7 10 21 9 33 6.0 0 0 0 1 8 4 67 8.0 0 0 0 3 27 20 30 Total 5 18 28 39 85 48 177 129 listed in Table 4.9. Only 14 out of 320 cases had errors above 30 percent but they did not exceed 40 percent. These cases occurred when tx value was 3.0 in. (10 cases) and 4.5 in. (4 cases). Table 4.9 also shows that only six cases with 20 to 30 percent predictive error occurred for tx value of 6.0 and 8.0 in. More importantly, the percent error decreased substantially for tx equal to 8.0 in. The majority of the pavements with 8.0 in. asphalt concrete thickness had less than 10 percent prediction error. The general tendency for Equations 4.18 and 4.19 was to predict with a higher degree of accuracy for pavements with thick asphalt concrete layers. Because of the high prediction errors from 3.0 in. asphalt concrete pavements, all the 3.0 in. pavements were also deleted from the data set. Subsequent regression analysis of the remaining data set yielded Equation 4.20, with a significantly improved correlation (R2 = 0.993, and N = 240). Error analysis revealed that only 2 out of 240 cases had errors of 20 percent or more. Pavements with E predictions having errors of 15 percent or more are listed in Table 4.10. This table indicates that only the 4.5- and 6.0-in. pavements fall in this category. The 4.5-in. pavements all underpredicted Ex when the actual value was 1200 ksi. However, for the 6.0-in. pavements, Ex values of 150 and 300 ksi were generally overpredicted. Again, predictions were very good for the 8.0-in. asphalt concrete pavements. This supports the findings with the Dynaflect that for thicker pavements, the effect of tx on E is small. 4.4.2.2 Base Course Modulus, E2 Two equations were derived to predict the base course modulus using theoretical 9-kip FWD load deflec tions. Equation 4.21, which was developed from a subset of the data 130 Table 4.9 Prediction Accuracy of Equation 4.19-' as a Function of tl -Error Distribution *1 Number of Cases With Percent Error Within (in.) > 60 50-60 40-50 30-40 20-30 15-20 < 15 3.0 0 0 0 10 7 9 54 4.5 0 0 0 4 12 12 52 6.0 0 0 0 0 5 19 56 8.0 0 0 0 0 1 2 77 Total 0 0 0 14 25 42 239 131 Table 4.10 Pavements with Ex Predictions Having 15 Percent or More Error (Equation 4.20Case 3) No. Layer Modul i E! E2 (ksi) E3 E4 *1 (in.) Predicted E. (ksi) Percent Difference 1 1200 42.5 30 5 4.5 951.7 -20.7 2 1200 42.5 30 10 4.5 976.8 -18.6 3 1200 42.5 30 20 4.5 1013.2 -15.6 4 1200 42.5 60 5 4.5 960.3 -20.0 5 1200 42.5 60 10 4.5 977 -18.6 6 1200 42.5 60 20 4.5 996.8 -16.9 7 1200 85. 30 5 4.5 966.1 -19.5 8 1200 85. 30 10 4.5 995.4 -17.0 9 1200 85. 30 40 4.5 976.1 -18.7 10 1200 85. 60 5 4.5 985.4 -17.9 11 150 42.5 30 20 6.0 174.3 16.2 12 300 42.5 30 20 6.0 349.5 16.5 13 150 42.5 30 40 6.0 175.5 17 14 300 42.5 30 40 6.0 351.5 17.0 15 300 42.5 60 10 6.0 346.7 15.6 16 300 42.5 60 40 6.0 347.8 15.9 132 set, had an R2 of 0.962 for 240 number of cases. Error analysis indi cated that 11 out of the 240 cases had errors exceeding 20 percent, and these were cases with tx equal to 1.5 or 6.0 in. These were the extremes of the range of tx used to develop Equation 4.21. When the data set was expanded to include tx and E4 values of 8.0 in. and 5.0 ksi, respectively, Equation 4.22 was obtained. This equa tion had an R2 of 0.953 for 400 number of observations. Error analysis indicated that 30 out of 400 observations had predictive errors above 20 percent. These simulated pavements are listed in Table 4.11, which shows that two pavements (numbers 24 and 28) had E2 predictions with 30 to 40 percent error. One pavement (number 27) had 54 percent prediction error. When all three pavements with 30 percent or more predictive errors were deleted from the data set, the R2 value increased from 0.953 to 0.956. This increase was considered not significant enough to war rant changing the Equation 4.22 format. The most interesting thing from Equation 4.22 was that most of the errors occurred at the extreme limits of tx (1.5 and 8.0 in.). As shown in Table 4.11, most of these high errors were pavements with E2 values of 42.5 and 175.0 ksi. Predictions were generally good for intermediate t1 values, especially 4.5 and 6.0 in. Moreover, Equation 4.22 contains sensor 8 deflection measurement (Dg) which is currently not made with the conventional sensor array utilized by the FD0T. Therefore, the reliability of this equation is contingent upon measurement of 0o. In o the absence of D measurement, Equation 4.21 would be the best choice 8 for prediction of the base course modulus. 4.4.2.3 Stabilized Subgrade Modulus, E^. Two equations were also developed to predict E3. Equation 4.23 which holds for t values from 133 Table 4.11 Pavements with E. Predictions Having 20 Percent or More Errors (Equation4.22--Case 2) No. Layer Moduli (ksi) E1 E2 E3 E4 *1 (in.) Predicted E. (ks1) Percent Difference 1 150 170. 30 5 1.5 133.9 -21.2 2 300 170. 30 5 1.5 127.9 -24.8 3 150 85. 60 5 1.5 109.7 29.1 4 300 170. 30 10 1.5 134.5 -20.9 5 150 85. 60 10 1.5 107.4 26.3 6 150 120. 60 10 1.5 145. 20.8 7 150 170. 30 20 1.5 133.7 -21.4 8 150 85. 60 20 1.5 102.5 20.6 9 150 42.5 30 40 1.5 33.5 -21.2 10 150 170. 30 40 1.5 128.9 -24.2 11 300 170. 30 40 1.5 128.4 -24.5 12 300 170. 30 5 3.0 135.2 -20.4 13 150 120. 60 10 3.0 144.5 20.4 14 150 170. 30 5 8.0 132.4 -22.1 15 300 42.5 30 5 8.0 52.2 22.9 16 300 42.5 60 5 8.0 54.6 28.4 17 300 60. 60 5 8.0 72.3 20.4 18 300 120. 60 5 8.0 144.1 20.1 19 300 170. 60 5 8.0 214.1 26.0 20 150 170. 30 10 8.0 131.9 -22.4 21 300 42.5 30 10 8.0 54.7 28.6 22 150 170. 60 10 8.0 133.8 -21.3 23 300 42.5 60 10 8.0 53.5 25.8 24 300 42.5 30 20 8.0 56.5 33.0 25 150 170. 60 20 8.0 128.8 -24.3 26 150 42.5 30 40 8.0 54.5 28.2 27 300 42.5 30 40 8.0 65.4 54. 28 300 60. 30 40 8.0 78.5 30.8 29 150 170. 60 40 8.0 134.2 -21.1 30 300 42.5 60 40 8.0 53.9 26.9 134 1.5 to 6.0 in. had an R2 of 0.958 with 192 number of cases analyzed. Error analysis indicated that only 9 out of the 192 total cases had predictive errors above 15 percent but all did not exceed 20 percent. These occurred in pavements with value of 40 ksi and tx of 1.5 or 6.0 in. Because of the high reliability of Equation 4.23, the database was expanded to include other moduli and thickness combinations. Analysis of the large data set (N = 400) resulted in Equation 4.24 with an R2 of 0.935. In 62 out of 400 cases, predictive errors were more than 20 per cent. Three pavements had 40 percent or more prediction errors with one of the them being 55.6 percent. Additional evaluation of the practical limits of Equation 4.24 indicated that prediction accuracy was satisfactory even when the Ex range was expanded to 600 ksi. Errors were generally less than 30 per cent and only 7 out of 80 cases had predictive errors between 30 and 43 percent using Ex = 600 ksi. Overall assessment of this E3 prediction suggests that the best accuracy is obtained from 3 to 6 in. of asphalt concrete. 4.4.2.4 Subgrade Modulus, E,. Five equations were derived to pre dict subgrade modulus from the 9-kip FW0 load deflections. The first three equations (4.25 to 4.27) were essentially dependent upon individ ual sensor deflections, Dg to D8, respectively. The other equations (4.28 and 4.29) included two sensor deflections in each equation. All five equations had R2 values greater than 0.997 for N = 400. Considering the high R2 values obtained for Equations 4.25 through 4.29, their prediction accuracy is expected to be good. Also, a high degree of accuracy is required for E^ prediction since small changes 135 would affect the FWD deflections and vice versa (see Section 4.2). Error analysis of these equations revealed that predictive errors were generally below 20 percent, with most cases actually being less than 10 percent. The highest errors occurred with Equation 4.25, and the least in Equation 4.29. This trend was in agreement with that of the R2 values. The lowest and least number of prediction errors always occurred using the equations with Dg as an independent variable(s). These are Equations 4.27 and 4.29. The FWD sensor for D measurement is located o 72.0 in. from the center of the loading plate and is not a conventional sensor spacing. The high degree of prediction accuracy with this sensor deflection emphasizes the need to incorporate its measurement in the FWD test system. However, in the absence of Dg, Equation 4.28 which incor porates both Dg and D? would be the best equation compared to the others. With the use of two sensor deflections, this equation should minimize the potential for prediction error due to measurement variability. CHAPTER 5 TESTING PROGRAM 5.1 Introduction The field testing program involved the acquisition of Dynaflect, Falling Weight Deflectometer (FWD), cone penetration test (CPT), Mar- chetti Dilatometer test (DMT), and plate bearing test data from selected sections of asphalt concrete pavements in the state of Florida. The test sections generally incorporated a wide range of deflection charac teristics resulting from the properties of the materials in the pavement layered systems. The NDT data generally served as a tool for assessing the applica bility of the prediction equations presented in Section 4.3 to actual field-measured NDT data. Also the deflection data were used to deter mine the actual moduli of the pavement systems at the time of NDT testing. The penetration tests also provided a means of determining layer thicknesses and moduli profiles. In addition, the CPT and DMT were used to evaluate the stratigraphy of the subsurface. This infor mation is valuable when performing elastic layer analyses to determine the moduli of pavement layers from NDT data. Details pertaining to testing procedures are presented in the ensuing discussion. Specific test areas for selected pavements were chosen on the basis of uniformity in response characteristics as determined from preliminary NDT measurements. More than one test site (section) was established when significant differences in NDT deflection response were observed 136 137 over the length of a highway pavement. The characteristics of each test section are described in detail in Section 5.2. Cores of the asphalt concrete layer were also obtained for labora tory tests on the rheological properties of the recovered asphalt. The rheology tests generally consisted of establishing the low temperature- viscosity characteristics of the recovered asphalt (117) which were then used to predict the modulus of the asphalt concrete layer. Other perti nent data collected as part of this program include the location of water table, pavement temperatures, and physical properties of the base, subbase, and subgrade soil materials. Detailed information on these testing procedures are presented in this chapter. 5.2 Location and Characteristics of Test Pavements Most of the pavement sections used in the study had been scheduled for evaluation by the FDOT. These sections, as listed in Table 5.1, are representative of pavement deflection response, type of construction, and soil-moisture conditions. Also shown in Table 5.1 are the year each pavement was originally built and the last time it was resurfaced with an overlay. Figure 5.1 shows the locations of the test pavement sec tions on the map of Florida. The thicknesses of surface and base layers for each pavement sec tion are also listed in Table 5.1. The asphalt concrete thickness was generally within the range listed in Table 4.1 for the theoretical anal ysis. However, the base course thickness differed slightly from the 8.0 in. used in Table 4.1, except for the 24 in. at the SR 715 test site. The subbase thicknesses were generally found to be 12.0 in., except for 138 Table 5.1 Characteristics of Test Pavements Test Road County Mile Post Number Year* Pavement Thickness (in.) Water Table AC Base (in.) SR 26A Gilchrist 11.8-12.0 1930(1982) 8.0 9.0 62 SR 26B Gilchrist 11.1-11.3 1930(1982) 8.0 7.5 44 SR 26C Gilchrist 10.1-10.2 1930(1982) 6.5 8.5 33 SR 24 Alachua 11.1-11.2 1976 2.5 11.0 NE** US 301 A1achua 21.5-21.8 1966 4.5 8.5 45 US 441 Columbia 1.2- 1.4 1960 3.0 9.0 NE I-10A Madison 14.0-14.1 1973(1980) 8.0 10.4 NE I-10B Madison 2.7- 2.8 1973(1980) 7.0 10.2 NE I-10C Madison 32.0-32.1 1973(1980) 5.5 10.2 NE SR 15A Martin 6.5- 6.6 1973 8.5 12.5 65 SR 15B Martin 4.8- 5.0 1973 7.0 12.0 65 SR 715 Palm Beach 4.7- 4.8 1969 4.5 24.0 NE SR 12 Gadsden 1.4- 1.6 1979 1.5 6.0 NE SR 80 Palm Beach Sec. 1 & 2 1986 1.5 10.5 NE SR 15C Martin 0.05- 0.065 1973 6.75 12.5 NE * Year represents the approximate date the road was built. Dates in parentheses are the latest year of reconstruction-overlay, surface treatment, etc. ** Water table not encountered at depth up to 18 ft. Measurements were made using a moisture meter inserted in the holes produced from cone penetration test (CPT). j'-O'*'* CJ Figure 5.1 Location of Test Pavements in the State of Florida 140 the SR 24 and SR 80 test sites where construction drawings indicated thicknesses of 17.0 in. and 36.0 in., respectively. The base course material consisted of limerock except for SR 12 which was constructed with a sand-clay mixture. The subbase material was in most cases stabilized, either mechanically or chemically with lime or cement. This layer is conventionally called "stabilized sub grade" by the FOOT. The underlying subgrade soils were generally sands with clay/silt layers often encountered at depth, as indicated from the penetration tests. The locations of the water table which were inferred from the CPT holes are also listed in Table 5.1. Most of the pavement sections were uncracked or had limited (hair line) longitudinal and/or transverse cracking. However, the US 441 test section did exhibit block cracking even though the pavement structure was stiff. Also SR 80, a recently constructed highway was included in the study for the following reason. Some segments were highly dis tressed due to construction problems which had resulted in potholes, ponding of water and cracking of the asphalt concrete surface. There fore, two segments of this roadway were included in this study; Section 1 in which there was no visible surface distress, and Section 2 in which cracks and potholes were present. Only Dynaflect test data was collec ted on SR 80. 5.3 Description of Testing Procedures 5.3.1 General Figure 5.2 shows the array and layout of tests performed for most of the test pavement sections. In general, the NOT tests were performed at 25-ft. spacings, while the penetration tests were restricted to sites / / 3 4 5 6 7 8 9 10 1 2 0 / 11 12 1 1 i i 1 i / I i 1 i i 1 i i \4 25'] \+\2*\ 1, 12 Q 0 / / / / FWD and Dynaflect Tests. Cone Penetration Tests. Marchelti Dilatometer Test. Trench for Plate Loading Test. Figure 5.2 Layout of Field Tests Conducted on Test Pavements 142 exhibiting uniformity in Dynaflect deflection measurements. Table 5.2 lists those tests performed on each test pavement section. 5.3.2 Dynaflect Tests Testing with the Dynaflect was accomplished using the standard sensor spacing to identify segments of pavement with fairly uniform deflection response. Each segment was tested at 25-ft. spacings until three or more locations provided essentially identical deflection basins. The modified Dynaflect sensor array was then used to obtain deflection measurements. The sensors were positioned by hand at loca tions designated as 1, 4, 7, and 10, as shown in Figure 4.2. These were the best positions, based on the theoretical study, for separation of layer response. The initial part of the field testing involved placing the extra sensor at position 9 in the modified system (standard position 4). This procedure was later changed to placing one sensor near each Dynaflect loading wheel and the remaining sensors placed at modified positions 4, 7, and 10. In the later case, an average value of Dx was used in the analysis. Appendix A lists Dynaflect deflection measurements from each test section. 5.3.3 Falling Weight Deflectometer Tests The FWD measurements were conducted at approximately the same loca tions as the Dynaflect. In the tests the height of drop and the weight were adjusted to produce different load levels. Two to three drops (load levels) were usually made, with the highest load often repeated. The highest load was generally close to 9 kips. The exact magnitude of each load applied was registered by a load cell located just above the loading plate. 143 Table 5.2 Summary of Tests Performed on Test Pavements Test Road Test Date Types of Tests Performed Dynaflect FWD CPT DMT PLT Rheology SR 26A 10-31-85 X X X X 0 X SR 26B 11-05-85 X X X X 0 X SR 26C 11-05-85 X X X X 0 X SR 24 12-03-85 X X X 0 0 X US 301 02-18-86 X X X X X X US 441 02-26-86 X X X X X X I-10A 03-18-86 X X X 0 X X I-10B 03-25-86 X X 0 0 X X I-10C 03-26-86 X X 0 0 X X SR 15A 04-28-86 X X 0 X 0 X SR 15B 04-28-86 X X X X 0 X SR 715 04-29-86 X X X X 0 X SR 12 08-12-86 X X X X X 0 SR 80 08-19-86 X 0 0 0 0 0 SR 15C 09-30-86 X X X X 0 X X Test performed 0 Test not performed 144 Deflections were measured with geophones at the conventional posi tions used by the FDOT. The measurements were made at radial distances of 0, 7.87, 11.8, 19.7, 31.5, 47.2, and 63.0 in. from the center of the FWD loading plate. It was not feasible to obtain deflection measure ments at sensor 8 (radial distance of 72.0 in.), although D8 had been used in developing some of the FWD layer moduli prediction equations. Appendix B lists test results for each test pavement section. 5.3.4 Cone Penetration Tests The cone penetration test consisted of penetrating the pavement at a rate of 2 cm/sec with an electronic friction cone. The University of Florida cone truck was used to conduct the tests. Three to four CPT soundings were conducted, spaced in between the NDT test locations, as illustrated in Figure 5.2. Each test was performed to a depth of approximately 18 ft., unless bedrock or a hard layer was encountered. Values of tip resistance, local friction, and friction ratio were obtained. The CPT data were generally collected from the surface of the asphalt concrete layer through the pavement to the final depth of exploration. Generally the 15 metric ton cone was used to conduct the CPT tests, especially in testing through the asphalt concrete and base course layers. The data acquisition system was used to obtain plots of the CPT test results. Appendix C shows profiles of tip resistance, local friction, and friction ratio for the tests conducted on each test pavement. The hole created by the CPT was used to determine the loca tion of the water table. This was performed by inserting a moisture meter into the hole. Table 5.1 lists the depth of water table for each test site. 145 5.3.5 Dilatometer Tests The dilatometer test was conducted according to the procedures described by Marchetti and Crapps (69). The University of Florida cone truck was also used to advance the dilatometer blade into the ground. Two to three DMT tests were conducted at each pavement test section. These were staggered between the CPT holes (Figure 5.2). Each test was also restricted to a depth of about 18 ft. The DMT tests were conducted only in the subbase and underlying subgrade soils. Because of the high stiffness of the overlying asphalt concrete and base course layers, these materials had to be cored out before conducting the DMT tests. The DMT data were reduced and inter preted with the computer program described by Marchetti and Crapps (69). The results of the DMT data reduction for each test are listed in Appendix D. 5.3.6 Plate Loading Tests The plate loading test was conducted on a limited number of test pavements as shown in Table 5.2. The testing procedure generally followed ASTM D 1195-64 (8) with slight modifications. The asphalt concrete layer was removed from approximately a 4-ft. wide strip across the traffic lane. In making the trench site, great care was taken to prevent disturbance of the material in the layer to be tested. The 12-in. plate was placed at a location within the test area. Molding plaster (hydrocal) was used to insure uniform loading on a level surface. The loading system was placed over the plate center. Two deflection gauges, one on each side of the 12-in. plate were then zeroed. The load increments depended upon the total load which was expected to cause an approximate 0.03-in. deflection. Five load levels 146 between the initial zero and the final 0.03-in. deflection were obtained during the test. Three cycles of loading were applied at each load level. After each load increment was applied, the load and deflection readings were recorded as soon as the gauge movement had stabilized. With this load in place, the next load increment was applied until the average deflection of the two gauges reached the 0.03 in. The load was then released and readings of any permanent deformation was recorded. All gauges were then zeroed and the above preloading sequence repeated two more times. After the third preload, the load was then increased in increments until a total deflection of 0.05 in. was reached. This deflection and corresponding load were then recorded. This process was repeated on the base, subbase, and subgrade layers. In all cases nuclear density tests were conducted, and soil samples were taken for moisture content and soil classification tests. A plot of load versus deflection was made to establish the linear ity of the load-deflection response. The modulus of elasticity (E) was then calculated using the following equation: E = 1.18 Eqn. 5.1 where A = deflection of 0.05 in. p = total load at the 0.05 in deflection in psi. a = radius of plate (6.0 in.). 147 The modulus values calculated from Equation 5.1 for each layer are essentially surface or composite modulus for the particular layer and the underlying layer(s). Burmister's two layer theory (133, pp. 40-44) was then used to obtain the modulus of each layer. Table 5.3 lists results of the plate loading tests. 5.3.7 Asphalt Rheology Tests The core samples of asphalt concrete obtained from each test pave ment section were separated in the laboratory according to each layer (lift) or type of asphalt concrete mix. These were then heated and broken down for extraction using Method B (Reflux) of ASTM D 2172 for Quantitative Extraction of Bitumen from Bituminous Paving Mixtures (8). The asphalt cement was recovered using the Abson method, ASTM D 1856 (8). Low-temperature rheology tests were performed at different tempera tures on the recovered asphalt cement samples. This involved viscosity determination at different shear stresses and test temperatures using the Schweyer Constant Stress Rheometer. Details pertaining to the physical characteristics, operation, and computational methods of the Schweyer Constant Stress Rheometer are presented by Tia and Ruth (117). Absolute and constant power viscosities (117) were computed from Schweyer Rheometer test data at temperatures of 140, 77, 60, 41, and 23F. The results for each test pavement site are listed in Appendix E. Linear regression analyses of constant power viscosity (n ) with 10 0 absolute temperature resulted in regression constants as listed in Table 5.4. These were then used in previously established modulus-viscosity- temperature relationships (98,117) to compute the modulus of the 148 Table 5.3 Plate Loading Test Results Test Road Mile Post No. Layer Type Layer Thickness (in.) Composite Modulus (ksi) Layer Modulus (ksi) Base 8.5 28.92 55.96 US 301 21.583 Subbase 12.0 18.65 27.75 Subgrade S.F.* 11.56 11.56 Base 9.0 28.42 40.31 US 441 1.236 Subbase 12.0 20.16 29.70 Subgrade S.F. 11.60 11.60 Base 10.4 48.20 93.77. , I-10A 14.062 Subbase 12.0 26.79 Subgrade S.F. 31.80 32.80 Base 10.1 34.68 80.13, . (a) I-10B 2.703 Subbase 12.0 20.03 Subgrade S.F. 21.16 21.16 Base 10.1 47.26 66.48 I-10C 32.071 Subbase 12.0 36.93 44.60 Subgrade S.F. 29.74 29.74 Base 6.0 28.30 43.42 SR 12 1.485 Subbase 12.0 25.54 46.10 Subgrade S.F. 15.37 15.37 * S.F. Semi-infinite layer (a) Deflection Factor, F2 (133, Fig. 2.7) greater than 1.0, thus calling for extrapolation. This would mean subbase layer weaker than subgrade or plastic deformation occurred during load test. 149 Table 5.4 Viscosity-Temperature Relationships of Recovered Asphalt from Test Pavements Test AC Description Regression Coefficients County Road Layer Mix Type a b R2 n 1 S-I 182.62 71.27 0.996 4 SR 26 Gilchrist 2 I 165.83 64.49 0.997 4 3 II 142.83 54.98 0.992 5 SR 24 A1 achua _ 166.49 64.85 0.999 5 179.70 70.13 0.996 5 1 II 152.81 59.18 0.994 5 US 301 A1 achua 2 3 I Binder 102.77 96.39 38.58 36.06 0.976 0.979 4 3 4 Binder 129.36 49.29 0.994 3 Surface I 96.39 36.06 0.979 3 US 441 Columbia 1 I 129.36 49.29 0.994 3 2 Binder 137.67 53.05 0.975 4 1 171.16 66.88 0.989 5 2 -- 162.95 63.55 0.999 4 I-10A Madison 3 -- 167.19 65.23 0.989 5 4 -- 144.87 56.01 0.989 5 5 171.54 69.12 0.998 4 1 _ _ 164.95 64.22 0.991 5 I-10B Madison 2 3 167.59 174.44 65.25 67.93 0.988 0.997 5 4 4 162.41 63.24 0.986 5 1 163.83 63.83 0.986 4 I-10C Madison 2 -- 148.83 57.58 0.983 5 3 154.79 60.03 0.985 5 1 Shell 155.38 59.99 1.000 3 2 Shell 105.57 39.73 0.966 4 SR 15B Martin 3 II 139.84 53.83 0.998 3 4 I 141.45 54.49 0.989 5 5 Shell 98.83 37.07 0.975 4 2 Shell 155.35 60.18 0.995 4 SR 15A Martin 3 4 II I 146.64 139.85 56.64 53.98 0.988 1.000 5 3 5 Shell 107.17 40.46 0.995 3 150 Table 5.4--continued Test AC Description Regression Coefficients* Road uuunujr Layer Mix Type a b R2 n SR 715 Palm Beach 1 2 I Shell 141.90 141.51 54.62 54.49 0.993 0.991 4 4 1 Shell 153.45 59.44 0.997 3 2 II 158.82 61.70 0.995 5 SR 15C Martin 3 S-I 157.73 61.25 0.996 5 4 Shell 144.24 55.71 1.000 3 5 Binder 153.69 59.53 0.981 3 * log n- = a b log T where n,- = constant power viscosity, n (Pa-sec) J 100 T = temperature in K (K = 273 + C) a, b = linear regression constants R2 = coefficient of determination n = number of observations used 151 asphalt concrete layer. Details pertinent to these calculations are described in the next chapter. 5.3.8 Temperature Measurements Temperature measurements were obtained for the air (ambient), the surface of pavement, and in the middle of the asphalt concrete pavement layer. These measurements were accomplished with the aid of a tempera ture probe. The mean asphalt pavement temperatures were taken using the probe to measure the temperature of motor oil that had been poured into a drilled hole in the pavement. The various temperature measurements are listed in Table 5.5. The mean pavement temperature measurements were necessary for the prediction of asphalt concrete moduli from the low-temperature viscosity data of the asphalts recovered from pavement cores (98,117). 152 Table 5.5 Temperature Measurements of Test Pavement Sections Test Mile Post Test Temperature (F) Road Number Date Air Surface Mean SR 26A 11.912 10-31-85 79 82 81 SR 26B 11.205 11-05-85 45 48 59 SR 26C 10.168 11-05-85 60 60 82 SR 24 11.102 12-03-85 57 55 57 US 301 21.580 2-18-86 63 65 69 US 441 1.236 2-26-86 51 56 79 I-10A 14.062 3-18-86 84 106 104 I-10B 2.703 3-25-86 80 101 88 I-10C 32.071 3-26-86 82 99 106 SR 15A 6.549 4-28-86 88 110 120 SR 15B 4.811 4-28-86 ' 93 111 127 SR 715 4.722 4-29-86 80 88 111 SR 12 1.485 8-12-86 81 91 102 SR 80 Sec 1 & 2 8-19-86 84 96 94 SR 15C 0.055 9-30-86 82 90 105 CHAPTER 6 ANALYSES OF FIELD MEASURED NDT DATA 6.1 General A complete description of the testing program has been presented in Chapter 5. The results of the field measured Dynaflect and FWD data are listed in Appendices A and B, respectively. These data were used with the prediction equations presented in Chapter 4 to determine the moduli of the pavement layers for the test sections. The analyses of the NDT data with regard to determining the elastic characteristics of the test pavements are presented in this chapter. 6.2 Linearity of Load-Deflection Response The underlying assumption in the theoretical analysis for the interpretation of NDT measurements is that each pavement layer acts as an isotropic, homogeneous, and linearly elastic medium. For this reason, a multilayered elastic computer program, BISAR, was used for the simulation and development of NDT and pavement layer moduli prediction equations, respectively. Therefore, the applicability of multilayered linear elastic theory to the test pavements is verified in this section. FWD measurements carried out at different load levels and tem peratures provided the means of checking whether it was feasible to adopt a linear elastic model to Florida's flexible pavement systems. The plot of load levels versus FWD deflections is a simple way to assess 153 154 linearity. Figures 6.1 through 6.14 shows surface deflection as a function of applied load, as obtained from the FWD tests, for all test sections except SR 80. FWD tests were not performed on this pavement section. The plots indicate that most of the test pavements (9 out of 14) had measured deflections showing strong linearity with the applied load for the seven different sensor locations. Test pavements exhibiting linear load-deflection response are SR 26A, SR 26C, SR 24, US 301, US 441, 1-10 A, B and C, and SR 715 as illustrated in Figures 6.1 to 6.9, respectively. However, it must be noted that the plots did not necessarily pass through the origin of the load-deflection diagrams. This would suggest that the load-deflection response was probably affected by other factors such as the initial static load in the FWD testing system. This will be explained later in this chapter. There were two other test pavements which showed a tendency towards linear load-deflection response with some slight deviations. These are SR 12 and SR 15C (Figures 6.10 and 6.11). For SR 12, Figure 6.10, the repeated test at the highest load level always produced lower deflec tions, especially for D., D and D However, the deflections measured at the fourth to seventh sensors showed close linearity to applied loads than the first three sensors. The decrease in deflection with repeated load on SR 12 could be due to seating effect, surface cracks, delayed recovery, and/or stiffening of the sand-clay materials beneath the thin (1.5-in. thick) asphalt concrete layer. Unlike SR 12, the first four sensor deflections measured at SR 15C showed strong linearity with the applied load (Figure 6.11). The last three sensors exhibited DEFLECTION (10 in) 155 Figure 6.1 Surface Deflection as a Function of Load on SR 26A 156 Figure 6.2 Surface Deflection as a Function of Load on SR 26C DEFLECTION (10 in) 157 Figure 6.3 Surface Deflection as a Function of Load on SR 24 DEFLECTION (103¡n) 158 Figure 6.4 Surface Deflection as a Function of Load on US 301 DEFLECTION (103¡n) 159 Figure 6.5 Surface Deflection as a Function of Load on US 441 o a DEFLECTION (10'3in) 160 MOA (Madison Co.) M.P. 14.062 1 2 4 6 FWD LOAD (KIPS) 7-^ Figure 6.6 Surface Deflection as a Function of Load on I-10A out DEFLECTION (10'3in) 161 Figure 6.7 Surface Deflection as a Function of Load on I-10B Q QQ 162 DEFLECTION (103in) 163 Figure 6.9 Surface Deflection as a Function of Load on SR 715 O O Q Q SENSOR DEFLECTION, 8¡ IN MILS 164 Figure 6.10 Surface Deflection as a Function of Load on SR 12 DEFLECTION (10'3¡n) 165 Figure 6.11 Surface Deflection as a Function of Load on SR 15C o o DEFLECTION (10 in) 166 Figure 6.12 Surface Deflection as a Function of Load on SR 26B DEFLECTION (lO"'5 in) 167 Figure 6.13 Surface Deflection as a Function of Load on SR 15A DEFLECTION (10*3¡n) 168 Figure 6.14 Surface Deflection as a Function of Load on SR 15B 169 nonlinearity like that of SR 26B. It is not known whether the anomaly on the SR 15C was caused by geophone sensitivity errors or possibly the sensors being placed on or near cracks in the asphalt concrete pavement. Three test pavements exhibited nonlinear response from the load- deflection diagrams. These are SR 26B, SR 15A, and SR 15B, as shown in Figures 6.12, 6.13, and 6.14, respectively. The SR 26B test section showed a stress-softening behavior in which deflections increased at a higher rate than the applied FWD load. The other two pavements, SR 15A and SR 15B, showed a stress-stiffening behavior from the FWD measure ments. Though, the plots of Figures 6.12 to 6.14 indicated that these pavements had a nonlinear response, a linear elastic model (BISAR) was used to analyze the behavior of all test pavements. The implications of this assumption are discussed in the following sections. 6.3 Prediction of Layer Moduli 6.3.1 General The developed equations presented in Section 4.3 were used to pre dict layer moduli for the test sections using the Dynaflect and FWD field measured deflections. Typical deflections were selected from each test site for the moduli computations. Predictions were performed for more than one test location when a test site showed excessive variabi lity in NDT deflections. Table 6.1 lists typical Dynaflect deflection data for the different test sections. The deflection data comprised of the modified and standard sensor configurations. Although the latter was not used in the prediction equations, it assisted in the initial analysis, especially in modeling the pavements. 170 Table 6.1 Typical Dynaflect Deflection Data from Test Sections Test Road Mile Post Number Deflections (mils) Di D3 6 7 D8 9 D,o SR 26A 11.912 0.87 0.81 0.77 0.68 0.61 0.53 0.45 0.39 SR 26B 11.205 1.28 1.18 1.23 1.12 0.99 0.90 0.77 0.68 SR 26C 10.168 0.89 0.77 0.77 0.62 0.53 0.37 0.24 0.16 SR 26C 10.166 0.90 0.77 0.78 0.68 0.54 0.44 0.27 0.17 SR 24 11.112 0.50 0.51 0.50 0.33 0.28 0.22 0.18 0.15 US 301 21.580 0.56 0.50 0.49 0.37 0.34 0.27 0.20 0.15 US 301 21.585 0.62 0.47 0.46 0.35 0.30 0.25 0.18 0.14 US 301 21.593 0.39 0.43 0.42 0.33 0.27 0.23 0.17 0.14 US 441 1.236 0.65 0.68 0.64 0.52 0.45 0.34 0.26 0.22 US 441 1.241 0.73 0.63 0.57 0.45 0.40 0.32 0.25 0.20 I-10A 14.062 0.30 0.29 0.28 0.18 0.16 0.10 0.07 0.05 I-10B 2.703 0.44 0.46 0.40 0.29 0.25 0.17 0.12 0.09 I-10C 32.071 0.70 0.46 0.43 0.30 0.29 0.22 0.18 0.15 SR 15B 4.811 1.10 1.03 1.04 0.91 0.92 0.82 0.75 0.66 SR 15A 6.549 1.50 1.46 1.48 1.40 1.36 1.27 1.14 1.04 SR 715 4.722 1.37 1.29 1.23 1.08 1.02 0.96 0.89 0.81 SR 715 4.720 1.45 1.38 1.36 1.15 1.19 1.07 1.00 0.91 SR 12 1.485 0.86 0.68 0.65 0.44 0.42 0.36 0.27 0.21 SR 80 Sec.l 2.11 2.02 1.89 1.61 1.48 1.37 1.07 0.85 SR 80 Sec.2 2.41 2.15 2.05 1.61 1.48 1.22 0.96 0.74 SR 15C 0.055 1.78 1.53 1.43 1.33 1.18 1.15 1.03 0.98 SR 15C 0.065 1.42 1.42 1.26 1.20 1.13 1.10 1.03 0.98 NOTE: Deflections are for both modified and standard geophone positions 171 FWD deflections from the highest load were used as input into the equations to predict layer moduli. However, these deflections were adjusted to equivalent 9-kip deflections to enhance the use of the prediction equations. Typical deflections, at the highest load level, were selected from each test site for the moduli computations. Table 6.2 lists the FWD deflections which have been adjusted to a 9-kip load level. 6.3.2 Dynaflect Layer Moduli Predictions The Dynaflect data listed in Table 6.1 were used with the appro priate equations to compute the respective layer moduli for each test pavement section. The prediction of Ex or E required an estimate of E2 or E respectively. Therefore, the modulus values which were later determined to be "true" moduli from modeling Dynaflect deflection basins were used as input to calculate the other modulus value (e.g., Ex or e2). For E3 computations, the simplified equation (Equation 4.15) was used for all test pavements without regard to the limitations of the equation. This was to illustrate that Equation 4.15 could be applied to a wider range without much problems. Three equations were used to com pute the subgrade modulus, E4. These are Equations 4.16 and 4.17, developed from the theoretical analyses, and Equation 4.35 which was originally developed from the analysis of field measured Dynaflect deflections on test pavements from Quebec, Canada and Florida. Table 6.3 lists layer moduli predictions from the Dynaflect equa tions. The asphalt concrete modulus, E using "true" E2 values as input were computed for most of the sections. Although most of the E2 172 Table 6.2 Typical FWD Data from Test Sections Test Road Mile Post No. Load (kips) Equivalent 9-kips Deflections (mils) * D! 2 3 4 5 6 7 SR 26A 11.912 9.08 10.41 8.52 7.24 5.55 3.96 2.68 2.18 SR 26B 11.205 9.096 10.79 9.70 9.00 7.72 6.33 4.75 3.76 SR 26C 10.168 9.008 13.39 11.39 9.89 7.49 4.80 2.60 1.60 SR 26C 10.166 8.936 13.90 11.38 10.07 7.65 5.04 2.82 1.81 SR 24 11.112 8.808 13.23 8.99 6.23 3.47 2.25 1.53 1.12 US 301 21.58 9.16 14.49 10.80 8.55 5.58 3.15 1.89 1.17 US 441 1.236 9.18 15.66 10.62 8.37 5.79 3.96 2.70 1.98 I 10A 14.062 9.116 8.01 4.32 3.33 1.89 0.84 0.44 0.35 I 10B 2.703 8.95 11.79 7.29 5.31 3.15 1.71 1.11 0.90 I IOC 32.071 9.008 10.26 7.47 5.76 3.51 2.07 1.26 0.90 SR 15B 4.811 8.962 18.47 13.13 10.76 8.22 6.45 5.06 4.04 SR 15A 6.546 9.280 21.80 15.77 13.78 11.08 8.67 6.84 5.46 SR 15A 6.549 9.026 14.41 12.32 11.27 9.81 8.13 6.52 5.33 SR 715 4.722 9.026 20.88 12.16 8.33 5.45 4.75 4.16 3.69 SR 715 4.720 8.803 16.38 10.91 8.01 5.80 4.95 4.35 3.86 SR 12 1.485 9.232 29.15 18.52 11.80 6.43 4.09 2.73 2.14 SR 15C 0.055 8.867 25.33 19.22 16.11 11.63 7.28 4.95 4.12 SR 15C 0.065 8.803 16.83 12.80 10.87 8.13 6.07 4.47 3.95 * Adjustment made on the assumption of linear load-deflection response 173 Table 6.3 Layer Moduli Using Dynaflect Prediction Equations Test Road Mile Post No. S (in.) Predicted Moduli (ksi) E (a) l e2 E (b) 3 E (c) 4 E (d) 4 E (e) 4 SR 26A 11.912 8.0 272.5 105.0 67.7 13.7 14.6 13.8 SR 26B 11.205 8.0 580.6 90.0 42.9 7.7 8.5 7.9 SR 26C 10.168 6.5 250.5 55.0 42.9 34.3 34.9 33.8 SR 26C 10.166 6.5 250.5 55.0 42.9 32.2 32.9 31.8 SR 24 11.112 2.5 * * 47.3 36.7 37.2 36.0 US 301 21.580 4.5 454.2 120.0 72.8 36.7 37.2 36.0 US 301 21.585 4.5 164.7 120.0 67.7 39.4 39.7 38.6 US 301 21.593 4.5 * 130.0 72.8 39.4 39.7 38.6 US 441 1.236 3.0 * 85.0 55.8 24.7 25.6 24.5 US 441 1.241 3.0 221.1 120.0 63.2 27.3 28.1 27.0 I-10A 14.062 8.0 1503.6 95.0 93.6 113.7 108.4 108.0 I-10B 2.703 7.0 740.0 80.0 72.8 62.1 61.1 60.0 I-10C 32.071 5.5 99.8 105.0 78.7 36.7 37.2 36.0 SR 15A 6.549 8.5 1474.0 120.0 93.6 5.0 5.6 5.2 SR 15B 4.811 7.0 452.8 120.0 93.6 8.0 8.8 8.2 SR 715 4.722 4.5 276.2 75.0 49.9 6.5 7.2 6.7 SR 715 4.720 4.5 533.3 65.0 63.2 5.7 6.4 5.9 SR 12 1.485 1.5 400.0 122.9 45.0 25.9 26.8 25.7 SR 80 Sec.l 1.5 100.0 132.4 23.5 6.1 6.9 6.4 SR 80 Sec. 2 1.5 100.0 72.3 16.2 7.1 7.8 7.3 SR 15C 0.055 6.75 72.4 105.0 41.0 5.3 6.0 5.5 SR 15C 0.065 6.75 165.8 105.0 85.5 5.3 6.0 5.5 a) Actual or calculated modulus b) E3 calculated from Equation 4.15 c) Equation 4.16 used to predict E4 d) Equation 4.17 used to predict E4 e) Equation 4.35 used to predict E4 * Prediction equations could not be used due to negative values of D, D, 174 values exceeded the range established for the Ex prediction equations, the predicted Ex values seem to be reasonable except for five test sec tions. For these sections (I-10A, I-10B, SR 15A and SR 715) the pre dicted asphalt concrete modulus tends to be high, considering the mean pavement temperature and corresponding viscosity of the asphalt binder during NDT testing. The reliability or accuracy of the predicted E2 values, neglecting estimation errors of E2, are discussed in Section 6.4. The base course modulus was computed for only three sites (SR 12, and SR 80 Sections 1 and 2, using an estimate of E Two of the pre dicted E2 values exceeded the limits originally established for the prediction equations (Case 4 Equations 4.8 to 4.10). The E3 predic tions seem to be reasonable and of the order of magnitude expected in practice. The accuracy of these values will be determined when the deflections are modeled using BISAR in Section 6.5. Table 6.3 shows that the three E4 predictions are in close agree ment, especially for Equations 4.16 and 4.35. The good agreement occurred for E4 values from 5.0 to about 40.0 ksi. However, beyond E^ values of 40.0 ksi, the agreement is good between Equations 4.17 and 4.35. A typical example is the I-10A test pavement in which the 108.4 and 108.0 ksi predictions from Equations 4.17 and 4.35, respectively, are far closer than that of 113.7 ksi from Equation 4.16. 6.3.3 FWD Prediction of Layer Moduli The FWD prediction equations and the deflection data listed in Table 6.2 were used to compute each layer modulus for the various test pavement sections. Equation 4.20 was used to make most of the E 175 computations, because the AC thickness generally exceeded 3.0 in. for most of the test pavements. Equation 4.19 was used for the SR 24 test site, while Equation 4.18 was used in the case of SR 12. The base course modulus, E2, was computed from Equation 4.21, since Equation 4.22, which was more generalized than Equation 4.21, could not be used because no D0 measurements were made during the FWD data collection. E was calculated from Equation 4.24. This equation was considered to be simplified enough and more generalized than Equation 4.23. Equations 4.25, 4.26, and 4.28 were used to make E4 computations. Equations 4.27 and 4.29 could not be used because measurements of D0 were not made during FWD testing. Table 6.4 lists the results of layer moduli predictions from the FWD prediction equations. The asphalt concrete modulus, E seems to be very high for most of the test sections. High Ex values are generally typical of pavements tested under cold temperature conditions and/or composed of very hard or brittle asphalt cements. The reliability or accuracy of the FWD predicted Ex values, and that of the Dynaflect, are compared in the next section with that determined from the rheology tests. The predicted E2 and E3 values seem to be of the order of magnitude expected in practice, with the possible exception of SR 26C and SR 715. For the latter, the high thickness of the base course layer (24.0 in.) might have caused the peculiar predictions of E2 and E3. There were also five test sections (SR 24, SR 15B, SR 715, SR 12, and SR 15C) in which the predicted E2 values were lower than that of E3. Also SR 26C, I-10A, US 301 and SR 15C test sections predicted considerably low E3 values. Unless the subbase layer of these pavements had failed, such 176 Table 6.4 Layer Moduli Using FWD Prediction Equations Test Road Mile Post No. *1 - (in.) Predicted Moduli (ksi) E (a) E (b) 2 E (c) 3 E (d) 4 ^(f) SR 26A 11.912 8.0 1278.0 53.0 27.0 19.8 18.5 17.8 SR 26B 11.205 8.0 1118.5 118.4 50.6 11.0 10.8 10.7 SR 26C 10.168 6.5 1312.0 121.4 5.7 20.4 25.1 28.5 SR 26C 10.166 6.5 295.6 166.6 7.6 18.8 22.2 24.6 SR 24 11.112 2.5 1451.0 20.3 65.1 35.2 35.8 36.1 US 301 21.580 4.5 508.7 64.4 11.0 28.3 34.2 38.4 US 441 1.236 3.0 200.0 58.4 39.8 19.6 20.4 20.8 I-10A 14.062 8.0 78.1 130.0 16.0 127.3 113.0 105.0 I-10B 2.703 7.0 216.3 44.0 20.7 49.0 44.4 41.8 I-10C 32.071 5.5 664.3 40.6 29.4 43.0 44.4 45.8 SR 15A 6.546 8.5 75.0 35.5 34.1 7.5 7.5 7.4 SR 15A 6.549 8.5 461.1 95.2 39.2 7.9 7.6 7.5 SR 15B 4.811 7.0 192.9 23.1 68.3 10.3 10.1 9.9 SR 715 4.722 4.5 161.2 9.4 300.3 12.6 11.0 10.6 SR 715 4.720 4.5 405.1 12.4 296.0 12.0 10.5 9.7 SR 12 1.485 1.5 2038.0 9.7 27.7 19.4 18.8 18.5 SR 15C 0.055 6.75 177.1 43.2 5.8 10.5 9.9 9.5 SR 15C 0.065 6.75 223.4 31.7 43.8 11.7 10.3 9.5 a) Equation 4.20 used to predict Ex except for SR 24 and SR 12 in which Equations 4.19 and 4.18, respectively, were used. b) Equation 4.21 used to predict E2# c) Equation 4.24 used to predict E3. d), (e) and (f) Equations 4.25, .4.26 and 4.28, respectively, were used to predict E4. 177 predictions could be considered to be in error. These will be verified when the FWD deflection basins are modeled using BISAR in Section 6.5. The subgrade modulus, E4, computed from the three applicable equa tions tends to be in favorable agreement for most of the test pavement sections. The agreement in the three equation predictions of E4 could be attributed to the high degree of accuracy of the developed equations. It can also be considered as an indicator of the homogeneity of the sub grade soils. Where they differed, for example, SR 26C, US 301, and I-10A, it is possible that the stiffness or strength of the underlying soils vary with depth. The lack of D8 measurements prevented means of assessing the equivalence of E4 predictions from the deflections at varying radial distances. It is postulated that knowledge of Dg, Dy, and D could assist in indicating the variability of the properties of O the subgrade soils with depth. Tables 6.2 and 6.4 suggest that small changes in deflections greatly affected the predicted moduli. This occurred on SR 26C, SR 15A, SR 715, and SR 15C test sections in which two adjacent deflection mneasurements were interpreted. However, the sensitivity analysis of Section 4.2 had indicated that large changes (50 and 100 percent) in E^, E2, and E3 did not have a large effect on FWD deflections. This was assessed by changing one variable while keeping the others fixed. It was not possible to assess the combined effect of the various layers on the deflections. However, the equations developed to predict Ej, E2, and E3 were dependent on almost all sensor deflection measurements. In this case, any changes in one or more sensor deflections would have a significant effect on the predicted modulus value. Therefore, the 178 equations for computing pavement layer moduli may be considered to be very sensitive to small changes in FWD deflections. 6.4 Estimation of Ex from Asphalt Rheology Data The predicted asphalt concrete modulus, E listed in Tables 6.3 and 6.4 were noted to be unusually high, considering the test tempera tures, for most of the test pavement sections. The equations used to compute these E values had a high degree of prediction accuracy from their R2 values. For example, Equation 4.20, used for most of the FWD predictions, had an R2 value of 0.993. The compatibility of the predic tion equations to the field measured NDT deflections is discussed in this and subsequent sections. As discussed previously, the resilient characteristics of asphalt concrete materials are generally dependent on both temperature and rate of loading. The modulus of asphalt concrete pavements are usually determined from indirect tensile tests (8) using either laboratory- prepared specimens or cored specimens from in-service pavements. An indirect method which uses low-temperature rheology tests and previously established correlations by Ruth et al. (98) has been found to effec tively predict asphalt concrete modulus, E1 (96,97,117). Asphalt cement samples recovered from the cores taken during NDT tests were tested to establish their viscosity-temperature relation ships. The results of the low-temperature rheology tests performed at different temperatures are listed in Appendix E. The resulting regres sion equations are also shown in Table 5.4. Using the mean pavement temperature recorded at the time of NDT tests, the corresponding E value was calculated using the procedures described by Tia and Ruth 179 (117). The following equations (98,117) were used in the computations: For n < 9.18 E8 Pa.s: 100 log E = 7.18659 + 0.30677 log(n ) Eqn. 6.1 1 100 For n > 9.19 E8 Pa.s: 100 log E = 9.15354 + 0.04716 log(n ) Eqn. 6.2 1 100 Equations 6.1 or 6.2 were used to compute E1 values for the various layers (lifts) in the AC layer. The average Ex value for the total AC layer was computed using the weighted average technique. Where lift thicknesses were not known, a common averaging technique was employed. The computed asphalt concrete moduli for the various test sections are listed in Table 6.5, and compared with those determined from the theo retically developed NDT prediction equations. Table 6.5 shows significant differences between the NDT and rheo logy methods. It will be shown in Section 6.5 that the indirect method which uses modulus-temperature-viscosity relationships is reliable in modeling NDT deflection basins. Therefore, the other Ex values deter mined from the NDT prediction equations could be doubtful. Higher differences occur with the FWD than the Dynaflect E1 predic tions. The discrepancy in the Dynaflect predictions could be attributed to the estimated E2 values exceeding the limits of developed equations and also the use of a single Dx measurement in most of the test sites. When two sensor deflection measurements are used (sensors placed next to 180 Table 6.5 Comparison Between NDT and Rheology Predictions of Asphalt Concrete Modulus Test Road Mile Post Number *1 (in.) Mean Temperature (F) AC Modulus, E(ksi) Rheology* Dynaflect FWD SR 26A 11.912 8.0 81 171.3 272.5 1278.0 SR 26B 11.205 3.0 59 406.5 580.6 1118.5 SR 26C 10.168 6.5 82 171.3 250.5 1312.0 SR 26C 10.166 6.5 82 171.3 250.5 295.6 SR 24 11.112 2.5 57 338.3 1451.0 US 301 21.580 4.5 69 256.6 454.2 508.7 US 301 21.585 4.5 69 256.6 164.7 573.5 US 441 1.236 3.0 79 289.6 200.0 US 441 1.241 3.0 79 289.6 221.1 1092.5 I-10A 14.062 8.0 104 60.8 1503.6 78.1 I-10B 2.703 7.0 88 113.2 740.0 216.3 I-10C 32.071 5.5 106 66.9 99.8 664.3 SR 15A 6.549 8.5 120 85.0 1474.0 461.1 SR 15B 4.811 7.0 127 90.5 452.8 192.9 SR 715 4.722 4.5 111 92.6 276.2 161.2 SR 715 4.720 4.5 111 92.6 533.3 405.1 SR 15C 0.055 6.75 105 80.3 72.4 177.1 SR 15C 0.065 6.75 105 80.3 165.8 222.3 * Weighted average values using Equations 6.1 and 6.2 181 each Dynaflect loading wheel), the potential for eccentric loading and its subsequent effect on Dx is reduced with the use of an average value from the two sensor deflections. In the case of the FWD, the prediction equations had a high degree of accuracy. Therefore, the suspect E values using FWD predictions could be affected by other factors which are discussed in the subsequent section. 6.5 Modeling of Test Pavements 6.5.1 General The theory of a linear elastic model generally implies that defor mations (or strains) are proportional to the loads applied to the medium or media. For flexible pavements, recoverable deformations are con sidered elastic even though they are not necessarily proportional to stress nor instantaneous. In accordance with the terminology first introduced by Hveem (48), recoverable deformations are referred to as resilient deformations and the corresponding moduli as resilient moduli. Analysis of the load-deflection response of the FWD measurements had indicated that a linear elastic model could be used to analyze most of the test pavements. Therefore, the BISAR elastic layer computer pro gram was used to determine the moduli of the pavement layers from the Dynaflect and FWD deflection basins. The subgrade was characterized as a composite value, as conventionally done in multi-layer analyses. The layer moduli determined from the prediction equations and summarized in Tables 6.3 and 6.4 were used as input into the BISAR computer program to compute Dynaflect and FWD deflections, respec tively. These modulus values plus layer thicknesses (Table 5.1) and Poisson's ratio (Table 4.1) served as input data for BISAR. The 182 interface conditions between layers were represented as perfectly rough (complete bonding). If the BISAR predicted deflections "closely" matched the measured deflections, then the input layer moduli were considered the correct pavement layer moduli which accurately model the pavement's NDT response. On the other hand if the measured and predicted deflections did not match, the input moduli values were adjusted until a suitable match of the measured deflection basin was achieved. This process of adjusting or "juggling" E-values is referred to, in this discussion, as tuning. However, this inverse technique of matching deflections does not yield unique solutions. Several moduli combina tions can produce the same deflection basin. This will be demonstrated in Section 6.5.4 using some of the test sections. Details pertaining to the modeling of the Dynaflect and FWD deflection basins of the test pavements are presented in Sections 6.5.2 and 6.5.3, respectively. 6.5.2 Tuning of Dynaflect Deflection Basins The layer moduli predictions listed in Table 6.3 were input into BISAR to predict Dynaflect deflections for comparison to the field measured values. Table 6.6 shows that the predicted deflections were very close to measured values with prediction errors of the order of 5 percent or less. However, there were some pavements with prediction errors as high as 30 percent, especially for Dx through Dg. These were the pavements (I-10A, I-10B, and SR 15A) which had considerably high E1 predictions. Therefore, the values were replaced by those predicted from rheology tests, as listed in Table 6.5, in modeling the Dynaflect deflection basins. 183 Table 6.6 Comparison of Field Measured and BISAR Predicted Dynaflect Deflections Dynaflect Deflections (mils) Road Number Type* D. 3 4 D6 7 D8 9 .o SR 26A 11.912 Measured Predicted 0.87 0.90 0.81 0.80 0.77 0.79 0.68 0.70 0.61 0.65 0.53 0.57 0.45 0.47 0.39 0.40 SR 26B 11.205 Measured Predicted 1.28 1.23 1.18 1.19 1.23 1.17 1.12 1.08 0.99 1.03 0.90 0.92 0.77 0.78 0.68 0.67 SR 26C 10.168 Measured Predicted 0.89 0.77 0.77 0.66 0.77 0.63 0.62 0.48 0.53 0.41 0.37 0.31 0.24 0.22 0.16 0.17 SR 26C 10.166 Measured Predicted 0.90 0.79 0.77 0.68 0.78 0.65 0.68 0.50 0.54 0.43 0.44 0.33 0.27 0.23 0.16 0.18 US 301 21.580 Measured Predicted 0.56 0.58 0.50 0.50 0.49 0.48 0.37 0.38 0.34 0.34 0.27 0.27 0.20 0.20 0.15 0.16 US 301 21.585 Measured Predicted 0.62 0.68 0.47 0.50 0.46 0.48 0.35 0.38 0.30 0.34 0.25 0.27 0.18 0.19 0.14 0.15 US 441 1.241 Measured Predicted 0.73 0.80 0.63 0.64 0.57 0.61 0.45 0.50 0.40 0.45 0.32 0.37 0.25 0.28 0.20 0.22 I-10A 14.062 Measured Predicted 0.30 0.23 0.29 0.22 0.28 0.22 0.18 0.17 0.16 0.15 0.10 0.11 0.07 0.08 0.05 0.05 I-10B 2.703 Measured Predicted 0.44 0.40 0.46 0.36 0.40 0.35 0.29 0.28 0.25 0.24 0.17 0.18 0.12 0.13 0.09 0.09 I-10C 32.071 Measured Predicted 0.70 0.76 0.46 0.49 0.43 0.47 0.30 0.38 0.29 0.34 0.22 0.27 0.18 0.20 0.15 0.16 SR 15B 4.811 Measured Predicted 1.10 1.00 1.03 0.94 1.04 0.92 0.91 0.85 0.92 0.81 0.82 0.74 0.75 0.65 0.66 0.58 SR 15A 6.549 Measured Predicted 1.50 1.04 1.46 1.03 1.48 1.02 1.40 0.98 1.36 0.95 1.27 0.90 1.14 0.83 1.04 0.76 SR 715 4.722 Measured Predicted 1.37 1.27 1.29 1.14 1.23 1.11 1.08 0.98 1.02 0.92 0.96 0.83 0.89 0.74 0.81 0.66 SR 715 4.720 Measured Predicted 1.45 1.28 1.38 1.19 1.36 1.16 1.15 1.03 1.19 0.96 1.07 0.87 1.00 0.77 0.91 0.70 SR 12 1.485 Measured Predicted 0.86 0.99 0.68 0.82 0.65 0.79 0.44 0.61 0.42 0.53 0.36 0.41 0.27 0.29 0.21 0.22 184 Table 6.6--continued Test Mile Post Dynaflect Deflections i (mils) Road Number Type* Di D3 D6 7 D8 9 D10 SR 80 Sec.l Measured Predicted 2.11 1.70 2.02 1.50 1.89 1.47 1.61 1.30 1.48 1.21 1.37 1.05 1.07 0.87 0.85 0.74 SR 80 Sec. 2 Measured Predicted 2.41 2.10 2.15 1.78 2.05 1.72 1.61 1.47 1.48 1.33 1.22 1.11 0.96 0.87 0.74 0.71 SR 15C 0.055 Measured Predicted 1.78 1.95 1.53 1.60 1.43 1.58 1.33 1.45 1.18 1.39 1.15 1.27 1.03 1.10 0.98 0.95 SR 15C 0.065 Measured Predicted 1.42 1.50 1.42 1.34 1.26 1.32 1.20 1.22 1.13 1.17 1.10 1.08 1.03 0.97 0.98 0.86 * Predicted using Dynaflect layer moduli predictions listed in Table 6.3 as input into BISAR. E4 predictions from Equation 4.35 were used. 185 Tuning of the test sections was accomplished by adjusting'the input moduli values until the BISAR predicted deflections closely matched the field measured Dynaflect deflections. Figures 6.15 through 6.31 illus trate measured and predicted deflection basins for all test sections. The plots show that agreement between predicted and measured deflections for SR 24, SR 12 and SR 80 (Section 2) as shown in Figures 6.18, 6.27, and 6.29, respectively, was poor. It is suspected that the lack of fit for these sites was probably due to the effects of variable foundation soils or non-visible cracks. For SR 80-Section 2, it is clearly known that the section had experienced problems including that of surface cracks (see Section 5.2). The layer moduli which produced the best fit of the measured Dyna flect deflection basins are called tuned moduli and are listed in Table 6.7. The corresponding Dynaflect deflections predicted from BISAR are listed in Table 6.8. Examination of the E values listed in Table 6.7 illustrates the good agreement between the final (or tuned) Ex values with that obtained from the use of the modulus-viscosity-temperature relationships. Slight adjustments occurred in the case of SR 268, SR 15A, SR 15B, and SR 15C. This could be due to the high mean pavement temperature (except SR 26B) and also possibly high air void contents of the asphalt concrete mixtures. Generally high air void contents tend to result in a reduction in measured Ex values using the rheology rela tionships. The actual air void contents of the mixtures were not known to apply the correction factors suggested by Ruth et al. (98). The other layer moduli values listed in Table 6.7 as the tuned moduli do not differ much from the predicted values of Table 6.3. This suggests the overall accuracy and reliabilty of the Dynaflect prediction DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.15 Comparison of Measured and Predicted Dynaflect Deflections for SR 26AM.P. 11.912 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.16 Comparison of Measured and Predicted Dynaflect Deflections for SR 26B--M.P. 11.205 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) 0 10 20 30 40 50 Figure 6.17 Comparison of Measured and Predicted Dynaflect Deflections for SR 26CM.P. 10.168 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.18 Comparison of Measured and Predicted Oynaflect Deflections for SR 24M.P. 11.112 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.19 Comparison of Measured and Predicted Dynaflect Deflections for US 301M.P. 11.112 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.20 Comparison of Measured and Predicted Dynaflect Deflections for I-10AM.P. 14.062 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (In) Figure 6.21 Comparison of Measured and Predicted Dynaflect Deflections for I-10BM.P. 2.703 DEFLECTION (mils) 50 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.22 Comparison of Measured and Predicted Dynaflect Deflections for I-10CM.P. 32.071 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) VO -Pi Figure 6.23 Comparison of Measured and Predicted Dynaflect Deflections for SR-15AM.P. 6.549 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.24 Comparison of Measured and Predicted Dynaflect Deflections for SR 15B-M.P. 4.811 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) O' Figure 6.25 Comparison of Measured and Predicted Dynaflect Deflections for SR 715M.P. 4.722 DEFLECTION (mils) 50 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.26 Comparison of Measured and Predicted Dynaflect Deflections for SR 715M.P. 4.720 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.27 Comparison of Measured and Predicted Dynaflect Deflections for SR 12M.P. 1.485 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) VO VO Figure 6.28 Comparison of Measured and Predicted Dynaflect Deflections for SR 80Section 1 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.29 Comparison of Measured and Predicted Dynaflect Deflections for SR 80Section 2 200 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) ro o Figure 6.30 Comparison of Measured and Predicted Dynaflect Deflections for SR 15CM.P. 0.055 DEFLECTION (mils) DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.31 Comparison of Measured and Predicted Dynaflect Deflections for SR 15CM.P. 0.065 202 203 Table 6.7 Dynaflect Tuned Layer Moduli for Test Sections Test Road Mile Post Number Layer Moduli (ksi) Ei E2 E 3 SR 26A 11.912 171.5 105.0 70.0 14.6 SR 26B 11.205 360.0 90.0 60.0 7.9 SR 26C 10.168 171.5 55.0 35.0 28.5 SR 24 11.112 338.3 105.0 75.0 38.6 US 301 21.580 250.0 120.0 60.0 38.6 US 301 21.585 250.0 120.0 75.0 42.0 US 301 21.593 250.0 130.0 80.0 44.0 US 441 1.236 290.0 85.0 60.0 27.5 US 441 1.241 290.0 120.0 75.0 28.5 I-10A 14.062 65.0 95.0 89.4 105.0 I-10B 2.703 113.0 80.0 65.0 60.0 I-10C 32.071 67.0 105.0 85.0 40.0 SR 15B 4.811 150.0 120.0 75.0 8.1 SR 15A 6.549 150.0 120.0 40.0 4.8 SR 715 4.722 92.6 75.0 50.0 6.0 SR 715 4.720 92.6 65.0 45.0 5.5 SR 12 1.485 400.0 120.0 75.0 26.5 SR 80 Sec.l 100.0 45.0 18.0 5.75 SR 80 Sec. 2 100.0 26.5 18.0 5.75 SR 15C 0.055 80.0 105.0 75.0 5.5 SR 15C 0.065 150.0 105.0 75.0 5.5 Table 6.8 Predicted Deflections from Tuned Layer Moduli Test Mile Post Deflections (mils) Road Number D l D 2 D 3 D 4 D 5 D 6 D 7 D 3 D 9 D 10 SR 26A 11.912 0.95 0.82 0.80 0.78 0.74 0.69 0.64 0.56 0.46 0.38 SR 26B 11.205 1.25 1.19 1.18 1.16 1.12 1.06 1.01 0.90 0.77 0.66 SR 26C 10.168 0.93 0.79 0.76 0.73 0.65 0.56 0.49 0.37 0.26 0.20 SR 24 11.102 0.62 0.50 0.47 0.45 0.40 0.35 0.31 0.25 0.19 0.15 US 301 21.580 0.65 0.54 0.52 0.50 0.45 0.39 0.34 0.27 0.19 0.15 US 301 21.585 0.59 0.49 0.46 0.44 0.40 0.35 0.31 0.24 0.18 0.14 US 301 21.593 0.56 0.46 0.44 0.42 0.38 0.33 0.29 0.23 0.17 0.13 US 441 1.236 0.85 0.71 0.68 0.64 0.58 0.51 0.45 0.36 0.27 0.21 US 441 1.241 0.73 0.62 0.59 0.57 0/52 0.46 0.42 0.34 0.26 0.20 I-10A 14.062 0.70 0.35 0.30 0.27 0.22 0.18 0.15 0.11 0.07 0.05 I-10B 2.703 0.66 0.45 0.42 0.39 0.34 0.28 0.24 0.18 0.13 0.10 I-10C 32.071 0.83 0.50 0.46 0.44 0.398 0.35 0.31 0.25 0.19 0.15 SR 15B 4.811 1.25 1.10 1.07 1.05 1.00 0.96 0.91 0.83 0.72 0.63 SR 15A 6.549 1.71 1.56 1.54 1.52 1.47 1.42 0.36 0.26 0.13 1.00 SR 715 4.722 1.57 1.31 1.27 1.23 1.17 1.10 1.05 0.96 0.86 0.76 SR 715 4.720 1.71 1.45 1.40 1.37 1.29 1.22 1.15 1.05 0.94 0.83 SR 12 1.485 0.87 0.73 0.70 0.67 0.61 0.54 0.48 0.38 0.29 0.22 SR 80 Sec 1 2.49 2.09 2.01 1.94 1.80 1.63 1.49 1.25 1.01 0.85 SR 80 Sec 2 2.92 2.30 2.16 2.07 1.87 1.67 1.50 1.25 1.01 0.86 SR 15C 0.055 1.77 1.49 1.45 1.42 1.37 1.31 1.26 1.16 1.03 0.91 SR 15C 0.065 1.56 1.41 1.38 1.36 1.31 1.26 1.20 1.11 0.99 0.88 ro o -P 205 equations. The results listed in Tables 6.7 and 6.8 will be used later in this chapter to develop simplified moduli prediction equations, espe cially in the case of and E2. 6.5.3 Tuning of FWD Deflection Basins The layer moduli predictions from the FWD equations and listed in Table 6.4 were also used as input into BISAR to compute the field measured FWD deflections. Table 6.9 compares measured and predicted FWD deflections. The table shows considerable differences between the two especially in Dx through D5 responses. In most cases there was a tendency to underpredict the deflections. Beyond D5, the agreement was generally good. This could be due to the fact that the predicted Ex values were too high to offset the influence of the underlying layer stiffnesses. Since Dg and Dy are mainly affected by E4, the good agree ment between measured and predicted deflections reflects the accuracy of the E4 prediction equations. The input moduli were adjusted until BISAR predicted deflections were in close agreement with measured values. Like the Dynaflect, Ex values used in the tuning process were those estimated from the rheology tests. Modeling of FWD deflection basins was found to be extremely difficult for most of the test sections. In general, it was relatively easy to match Dx and Dg or D?, and difficult to simulate the interme diate sensor deflections. This could be due to the accuracy of the Ex and E4 values compared to the other layer moduli predictions. Figures 6.32 through 6.49 illustrate the modeling of the test pavement sections using the FWD deflection basins. The deflections are normalized to 1-kip load level. The figures show that for some of the pavements such as US 441, SR 12, and SR 15C, the predicted deflections Table 6.9 Comparison of Field Measured and BISAR Predicted FWD Deflections Test Mile Post FWD (9-kip Load) Deflections (mils) Road Number Type* Di 2 3 4 5 6 7 SR 26A 11.912 Measured 10.41 8.52 7.24 5.55 3.96 2.68 2.18 Predicted 7.55 6.74 6.24 5.30 4.14 3.04 2.31 SR 26B 11.205 Measured 10.79 9.70 9.00 7.72 6.33 4.75 3.76 Predicted 8.82 8.01 7.55 6.72 5.67 4.56 3.70 SR 26C 10.168 Measured 13.39 11.39 9.89 7.49 4.80 2.60 1.60 Predicted 8.36 7.40 6.76 5.56 4.06 2.63 1.73 SR 26C 10.166 Measured 13.90 11.38 10.07 7.65 5.04 2.82 1.81 Predicted 10.77 8.45 7.44 5.92 4.21 2.70 1.82 SR 24 . 11.122 Measured 13.23 8.99 6.23 3.47 2.25 1.53 1.12 Predicted 15.61 10.38 7.14 3.49 1.94 1.41 1.09 US 301 21.580 Measured 14.49 10.80 8.55 5.58 3.15 1.89 1.17 Predicted 12.41 9.35 7.54 4.96 2.77 1.46 0.96 US 441 1.236 Measured 15.66 10.62 8.37 5.79 3.96 2.70 1.98 Predicted 15.98 10.04 7.62 5.34 3.73 2.58 1.93 I-10A 14.062 Measured 8.01 4.32 3.33 1.89 0.84 0.44 0.35 Predicted 11.28 5.14 3.60 2.33 1.28 0.62 0.37 I-10B 2.703 Measured 11.79 7.29 5.31 3.15 1.71 1.11 0.90 Predicted 11.19 7.60 5.96 3.84 2.22 1.31 0.93 I-10C 32.071 Measured 10.26 7.47 5.76 3.51 2.07 1.26 0.90 Predicted 8.73 6.60 5.31 3.43 1.94 1.15 0.84 SR 15B 4.811 Measured 18.47 13.13 10.76 8.22 6.45 5.06 4.04 Predicted 18.17 13.73 11.56 8.67 6.44 4.92 3.92 Table 6.9--continued Test Mile Post FWD (9-kip Load) Deflections (mils) Road Number Type* Di D2 3 5 6 7 SR 15A 6.546 Measured 21.80 15.77 13.78 11.08 8.67 6.84 5.46 Predicted 23.73 16.09 13.52 10.80 8.57 6.69 5.35 SR 15A 6.549 Measured 14.41 12.32 11.27 9.81 8.13 6.52 5.33 Predicted 11.70 10.17 9.47 8.41 7.23 6.01 5.04 SR 715 4.722 Measured 20.88 12.16 8.33 5.45 4.75 4.16 3.69 Predicted 36.59 25.36 18.76 10.48 5.77 4.16 3.48 SR 715 4.720 Measured 16.38 10.91 8.01 5.80 4.95 4.35 3.86 Predicted 24.54 18.90 15.20 9.83 6.02 4.37 3.65 SR 12 1.485 Measured 29.15 18.52 11.80 6.43 4.09 2.73 2.14 Predicted 33.19 20.55 13.33 6.55 4.03 2.75 2.05 SR 15C 0.055 Measured 25.33 19.22 16.11 11.63 7.28 4.95 4.12 Predicted 21.51 17.02 14.87 11.81 8.72 6.07 4.40 SR 15C 0.065 Measured 16.83 12.80 10.87 8.13 6.07 4.47 3.95 Predicted 17.25 13.37 11.46 8.89 6.77 5.18 4.11 * Predicted using FWD layer moduli predictions listed in Table 6.4 as input into BISAR. E predictions from Equation 4.28 were used. 207 NORMALIZED DEFLECTION (mils) 208 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.32 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 26A M.P. 11.912 NORMALIZED DEFLECTION (mils) 209 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.33 Comparison of Measured and Predicted FWD Deflections (Normalized to l-kip Load) for SR 26BM.P. 11.205 NORMALIZED DEFLECTION (mils) 210 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.34 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 26C--M.P. 10.168 NORMALIZED DEFLECTION (mils) 211 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.35 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 26C--M.P. 10.166 NORMALIZED DEFLECTION (mils) 212 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.36 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 24M.P. 11.112 NORMALIZED DEFLECTION (mils) 213 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.37 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for US 301M.P. 21.585 DEFLECTION (mils) 214 DISTANCE FROM CENTER OF LOAD AREA (in) Figure 6.38 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for US 441M.P. 1.236 NORMALIZED DEFLECTION (mils) 215 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.39 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for I-10AM.P. 14.062 NORMALIZED DEFLECTION (mils) 216 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.40 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for I-10B--M.P. 2.703 DEFLECTION (mils) 217 DISTANCE FROM CENTER OF LOAD AREA (in) Figure 6.41 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for I-10CM.P. 32.071 NORMALIZED DEFLECTION (mils) 218 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.42 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15AM.P. 6.546 NORMALIZED DEFLECTION (mils) 219 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.43 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15AM.P. 6.549 NORMALIZED DEFLECTION (mils) 220 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.44 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15BM.P. 4.811 NORMALIZED DEFLECTION (mils) 221 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.45 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 715M.P. 4.722 NORMALIZED DEFLECTION (mils) 222 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.46 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 715M.P. 4.720 NORMALIZED DEFLECTION (mils) 223 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.47 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 12M.P. 1.485 NORMALIZED DEFLECTION (mils) 224 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.48 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15CM.P. 0.055 NORMALIZED DEFLECTION (mils) 225 DISTANCE FROM CENTER OF LOADED AREA (in) Figure 6.49 Comparison of Measured and Predicted FWD Deflections (Normalized to 1-kip Load) for SR 15CM.P. 0.065 226 closely match measured values for all sensor locations. However, for most of the other pavements, especially SR 26C, I 10, and SR 715, the agreement between measured and predicted deflections was good for'D , Dg, and Dy measurements only. The difficulty in matching FWD deflec tions with BISAR could be due to one or more of the following: 1. The pavements did not necessarily behave as linear elastic media. 2. It was improper to represent the FWD impulse or dynamic loadings with a pseudo-static loading in BISAR. 3. Neglecting the inertia of the pavement in the simulation of NDT response using multilayered linear elastic theory. 4. The FWD plate and loading are rigid rather than flexible as assumed in the BISAR analysis. 5. The spacing of the geophones and loading configuration are probably not suitable to allow the separation of pavement layers during the interpretation of FWD deflections. It is believed that the above reasons, especially the first three apply to all NDT devices. It may be argued that the small load (1.0 kip total) in the Dynaflect system is too small to produce any sensitivity in the load-deflection response compared to the 9-kip load used in the FWD. On the other hand, the use of dual loads in the Dynaflect testing system with the modified sensor configuration enhances the separation of layer response. Differences between the response of the test pavements to the FWD and Dynaflect are discussed in detail in Section 6.6. The layer moduli which best matched one or more of the FWD deflec tions were selected as the pavement tuned layer moduli. These are listed in Table 6.10. The predicted FWD deflections using the tuned layer moduli are listed in Table 6.11. The tuned Ex values were not 227 Table 6.10 FWD Tuned Layer Moduli for Test Sections Test Road Mile Post Number Layer Modulus (ksi) Ei E2 E3 E4 SR 26A 11.912 171.5 75.0 45.0 18.7 SR 26B 11.205 360.0 90.0 45.0 11.0 SR 26C 10.168 171.5 45.0 27.5 25.5 SR 26C 10.166 171.5 55.0 22.0 20.0 SR 24 11.112 338.3 55.0 40.0 38.6 US 301 21.580 250.0 45.0 35.0 25.0 US 441 1.236 290.0 55.0 35.0 20.0 I-10A 14.062 100.0 90.0 80.0 130.0 I-10B 2.703 100.0 60.0 50.0 43.0 I-10C 32.071 120.0 85.0 50.0 46.0 SR 15B 4.811 90.5 52.8 50.0 10.2 SR 15A 6.546 85.0 45.0 35.0 7.0 SR 15A 6.549 150.0 95.0 39.5 7.5 SR 715 4.722 92.6 45.0 25.0 11.0 SR 715 4.720 92.6 65.0 26.0 10.5 SR 12 1.585 400.0 31.0 20.0 18.5 SR 15C 0.055 80.0 35.0 12.0 9.8 SR 15C 0.065 150.0 50.0 44.0 10.0 228 Table 6.11 Predicted FVJD Deflections from Tuned Layer Moduli Test Road Mile Post Number BISAR Deflections (mils) Di 2 3 D4 Ds 6 7 SR 26A 11.912 11.42 7.92 6.65 5.18 3.89 2.85 2.18 SR 26B 11.205 11.59 9.61 8.72 7.39 5.97 4.62 3.65 SR 26C 10.168 13.60 9.17 7.24 4.91 3.18 2.11 1.56 SR 26C 10.166 14.44 10.15 8.30 5.98 4.05 2.72 2.01 SR 24 11.112 13.55 7.73 5.29 3.24 2.06 1.38 1.03 US 301 21.580 14.18 9.53 7.28 4.78 3.13 2.12 1.58 US 441 1.236 16.12 10.58 8.08 5.60 3.87 2.67 1.99 I-10A 14.062 8.58 3.51 2.16 1.16 0.65 0.41 0.31 I-10B 2.703 11.97 6.30 4.50 2.88 1.89 1.26 0.94 I-10C 32.071 10.35 5.57 4.07 2.69 1.76 1.18 0.87 SR 15B 4.811 18.51 12.16 10.09 8.04 6.42 5.02 4.02 SR 15A 6.546 21.99 15.35 13.16 10.82 8.80 6.99 5.65 SR 15A 6.549 15.38 11.67 10.45 9.09 7.72 6.32 5.21 SR 715 4.722 19.95 12.39 9.74 7.36 5.76 4.47 3.57 SR 715 4.720 17.11 10.75 8.77 7.06 5.76 4.60 3.73 SR 12 1.485 29.54 16.64 11.29 6.84 4.26 2.81 2.09 SR 15C 0.055 25.38 17.35 14.30 10.80 7.82 5.49 4.08 SR 15C 0.065 16.60 12.05 10.24 8.14 6.42 4.98 3.97 229 much different from those obtained from the rheology tests (Table 6.5). This does not only confirm the reliability of the indirect method of predicting Ej, but also suggests that the E values obtained from the prediction equations are suspect. Also the tuned and E3 values are much different from the predicted values listed in Table 6.4. However, the subgrade modulus values compare well which emphasizes the uniqueness of the relationship between E4 and the furthest NDT sensor deflec tion^). The use of the field measured FWD deflections as input into the prediction equations did not yield reasonable layer moduli, especially for Ex. Predicted deflections were generally different from the field measured values and likewise the tuned moduli differed considerably from the predicted, with the possible exception of E4. It was suggested that this discrepancy was due to the fact that FWD measurements do not neces sarily satisfy the assumptions of layered theory used in the theoretical analysis. To support this, the predicted deflections obtained from BISAR using the tuned moduli were then used as input into the developed equations to compute the layer moduli. These deflections, listed in Table 6.11, are for all purposes BISAR generated deflections and should satisfy the assumptions inherent in the theoretical analysis. Table 6.12 lists the calculated (predicted) moduli compared with the tuned values. There is favorable agreement between the two for each layer modulus. For the SR 12 tests site, the considerable difference in E values is due to the poor prediction accuracy of Equation 4.18 for very thin asphalt concrete layers. The relatively good agreement between predicted and tuned moduli in Table 6.12 indicates that the prediction equations could be used to estimate layer modlui. However, 230 Table 6.12 Comparison Between Re-Calculated and Tuned FWD Layer Moduli Test Road Mile Post Number Tuned Moduli^1) (ksi) Predicted Moduli^2) (ksi) Ei E2 E3 E. Ei E2 E3 E4 SR 26A 11.912 171.5 75.0 45.0 18.7 167.4 65.5 51.4 18.5 SR 26B 11.205 360.0 90.0 45.0 11.0 340.0 117.8 48.0 11.0 SR 26C 10.168 171.5 45.0 27.5 25.5 194.6 49.1 26.7 26.0 SR 26C 10.166 171.5 55.0 22.0 20.0 188.3 59.2 23.7 20.4 SR 24 11.112 338.3 55.0 40.0 38.6 428.9 54.4 51.7 38.6 US 301 21.580 250.0 45.0 35.0 25.0 262.0 43.9 36.4 25.6 US 441 1.236 290.0 55.0 35.0 20.0 286.4 51.1 42.5 20.5 I-10A 14.062 100.0 90.0 80.0 130.0 91.2 66.0 57.4 122.0 I-10B 2.703 100.0 60.0 50.0 43.0 101.5 47.9 52.7 42.2 I-10C 32.071 120.0 85.0 50.0 46.0 113.9 81.6 56.7 45.8 SR 15B 4.811 90.5 52.8 50.0 10.2 90.5 35.8 69.0 10.0 SR 15A 6.546 85.0 45.0 35.0 7.0 84.1 27.5 51.8 7.1 SR 15A 6.549 85.0 95.0 39.5 7.5 74.0 39.3 79.4 7.6 SR 715 4.722 92.6 45.0 25.0 11.0 96.0 35.4 80.0 11.2 SR 715 4.720 92.6 65.0 26.0 10.5 90.7 51.5 115.0 10.6 SR 12 1.485 400.0 31.0 20.0 18.5 201.5 18.6 23.3 19.6 SR 15C 0.055 80.0 35.0 12.0 9.8 88.9 33.6 18.7 10.3 SR 15C 0.065 150.0 50.0 44.0 10.0 160.7 43.1 60.0 10.1 (1) BISAR tuned moduli (Table 6.10) (2) Moduli obtained using deflections in Table 6.11 as input into FWD prediction equations 231 to use the equations with field measured FWD deflections may result in substantial prediction errors. This suggests that the measured FWD deflections should be adjusted to compensate for the possible effects of the rigid plate and other variables prior to the application of the developed equations which were based on multilayered elastic theory. 6.5.4 Nonuniqueness of NDT Backcalculation of Layer Moduli One of the major problems associated with backcalculation of layer moduli from NDT deflection basins is the nonuniqueness of moduli. Theo retically, an infinite number of moduli combinations can produce the same deflection basin. There are no closed-form solutions at present to compute layer moduli if the NDT deflections are known. Therefore, a completely erroneous set of moduli could be determined for a pavement using the trial-and-error approach of matching measured deflection basins. This is demonstrated in Table 6.13 using field measured Dyna- flect basins from some of the test sections. Table 6.13 shows that for the US 301 test section, the use of two different combinations of Ex and E2 and same Eg and E^ values produced practically the same deflection basin. The Ex value of 250.0 ksi is that obtained from the modulus-viscosity-temperature relationships. However, an E1 value which is five times as high as the above value also produced similar deflections, with a slight reduction in E2. In the case of US 441, when the Ej value was reduced from 290.0 ksi to 100.0 ksi, predicted deflections were close to measured. It was initially believed that the extensive block cracking on this site (Sec tion 5.2) had caused the reduction in the asphalt concrete modulus as predicted from rheology data. However, because a third set of moduli combination produced similar deflections indicate that the problem could Table 6.13 Illustration of Nonuniqueness of Backcalculation of Layer Moduli from NDT Deflection Basin Test Layer Modul i (ksi) Dynaflect Deflections (mils) Road No.* E E E E D D D D D D D D l 2 3 4 l 3 4 6 7 8 9 10 0 0.56 0.50 0.49 0.37 0.34 0.27 0.20 0.15 US 301 1 250.0 120.0 60.0 38.6 0.65 0.52 0.50 0.39 0.34 0.27 0.20 0.15 2 1211.2 85.0 60.0 38.6 0.55 0.52 0.50 0.40 0.34 0.26 0.19 0.15 0 MB _ 0.65 0.68 0.64 0.52 0.45 0.34 0.26 0.22 US 441 1 290.0 85.0 60.0 27.5 0.85 0.68 0.64 0.51 0.45 0.36 0.27 0.21 2 100.0 85.0 60.0 27.5 0.97 0.69 0.66 0.52 0.46 0.37 0.27 0.21 3 290.0 120.0 60.0 25.5 0.80 0.67 0.64 0.53 0.47 0.38 0.29 0.23 0 __ 1.50 1.46 1.48 1.40 1.36 1.27 1.14 1.04 SR 15A 1 150.0 105.0 55.0 4.7 1.69 1.52 1.49 1.39 1.34 1.24 1.11 1.00 2 150.0 120.0 40.0 4.8 1.71 1.54 1.52 1.42 1.36 1.26 1.13 1.00 0 __ 0.87 0.81 0.77 0.68 0.61 0.53 0.45 0.39 SR 26A 1 171.5 105.0 85.0 14.0 0.98 0.82 0.80 0.71 0.66 0.57 0.47 0.39 2 171.5 105.0 65.0 14.5 0.97 0.81 0.79 0.70 0.65 0.56 0.46 0.39 3 171.5 105.0 70.0 14.6 0.95 0.80 0.78 0.69 0.64 0.56 0.46 0.38 * 0 Field-measured Dynaflect deflections 1,2,3 Tuned moduli and corresponding BISAR deflections 233 be due to nonuniqueness in the backcalculation of layer moduli. Table 6.13 also shows that slight changes in E3 and E4 (SR 15A and SR 26A) could also lead to the same deflection solutions. The problem of nonuniqueness in layer moduli determination is pre vented with the use of the prediction equations. The subgrade modulus has already been shown to be uniquely related to the deflection(s) at the farthest sensor in the Dynaflect and FWD testing systems. Also the high degree of reliability of predicting E1 from asphalt rheology rela tionship generally fixes the £l value to be used in the tuning of deflection basin. The use of the prediction equations in addition to E1 predictions from rheology tests eliminate guesswork in selecting initial moduli. Therefore the methodology presented in this dissertation ensures unique solutions and is not user-dependent with regard to selecting input moduli values. 6.5.5 Effect of Stress Dependency As previously mentioned, laboratory studies generally suggest that the moduli of subgrade materials and granular bases are stress depen dent. One of the advantages of the FWD testing system is its ability to apply variable and heavier loads to assess the stress dependency of pavement materials. The load-deflection response shown in Figures 6.1 through 6.14 indicated that FWD deflections were within reason linearly related to the applied loads for most of the test sections except for SR 26B, SR 15A and SR 15B. For these pavement sections, the tendency was toward a nonlinear response. However, in all cases the load-deflection response did not pass through the origin. This could be due to the inertia of the pavement system to loading, and perhaps the influence of the static loading due to the plate. 234 The stress dependency of the test pavements was evaluated by using FWD deflections at different load levels to compute the layer moduli. Five test pavements were selected for this analysis. Two of the pave ments (SR 24 and SR 12) showed close resemblance to linearity. The others were SR 26B which exhibited a stress-softening behavior; SR 15A and SR 15B which behaved as a stress-stiffening material from their load-deflection diagrams. The corresponding deflections measured at the different load levels were normalized to 9 kips load level. These are compared in Table 6.14 for each of the five test pavement sections. Table 6.14 shows that deflections measured at the lowest load are much different from the other high loads. This is especially true for SR 26B, SR 15A, and SR 15B in which the deflections produced by the lowest load are all less than those measured at the higher loads. Such a result would agree with the stress-softening behavior of SR 26B, and not for SR 15A and SR 15B, where a stress-stiffening phenomenon was postulated from the load-deflection diagrams. The deflections for SR 24 and SR 12 compare well and the slight differences could be due to the precision of the measuring devices, possibility of measuring close to non-visible surface cracks (in the case of SR 12), and also due to the resilient characteristics of the pavement materials. In general, there is consistency in the normalized deflections at the two or more higher loads even for the nonlinear pavements. Therefore, the nonlinearity behavior of SR 26B, SR 15A, and SR 15B test sections only occur at loads less than 6.0 kips. The deflections listed in Table 6.14 were used to predict the respective layer moduli. These were then input, using the E1 values from rheology data, into BISAR to tune the various deflection basins. Table 6.14 Comparison of Deflections Measured at Different Load Levels Test ! Mile Post Load Normalized Deflections* (mils) Road Number (kips) Di 2 3 4 5 6 7 4.760 14.94 9.45 6.05 3.03 1.89 1.32 0.95 SR 24 11.112 7.176 13.55 9.16 6.27 3.26 2.01 1.38 1.13 8.816 13.27 8.98 6.23 3.47 2.25 1.53 1.12 4.696 32.77 18.21 10.54 6.13 3.83 2.49 2.49 SR 12 1.485 6.920 29.52 18.08 11.19 6.63 3.64 2.47 1.82 9.232 29.15 13.52 11.80 6.43 4.09 2.73 2.14 9.288 28.68 17.44 11.24 6.30 4.17 2.71 2.33 4.656 8.12 6.77 6.38 5.03 3.67 2.51 1.55 SR 26B 11.205 6.880 10.33 9.16 8.50 7.33 5.89 4.45 3.53 9.096 10.79 9.70 9.00 7.72 6.33 4.75 3.76 9.112 10.57 9.48 8.79 7.51 6.12 4.64 3.65 4.656 12.33 10.50 9.51 8.14 6.63 5.34 4.47 SR 15A 6.551 7.008 15.27 13.29 12.09 10.42 8.54 6.73 5.67 9.026 15.46 13.46 12.21 10.44 8.48 6.55 5.26 4.513 16.65 10.99 8.24 6.04 4.87 4.17 3.53 SR 15B 4.811 6.769 18.84 13.30 10.75 8.00 6.24 5.03 4.08 8.962 18.47 13.13 10.76 8.22 6.45 5.06 4.04 * Deflections normalized to 9 kips load 236 The resultant layer moduli are listed in Table 6.15. The modulus of the asphalt concrete was generally found to be the same and close to the value determined from rheology data. The base course modulus, E2, decreased with load in the case of SR 15A and SR 15B test sections. This again confirms that the pavement materials were stress-softening rather than stress-stiffening. The subbase and subgrade layers had modulus values showing no particular trends, except that higher values were obtained at the lowest load. At higher loads the moduli for the subbase and subgrade layers were very consistent. Tables 6.14 and 6.15 suggest that FWD deflections should be mea sured at higher loads, preferably 9 kips to minimize the effects of nonlinearity. This also implies that equivalent moduli can be deter mined using the theory of elasticity. The equivalent moduli would, hopefully, produce a reasonable estimate of the deformations and strains in the field. 6.6 Comparison of NDT Devices The previous discussion indicated that different responses were observed with the Dynaflect and FWD deflection basins. These differ ences can be attributed to the magnitude of loading applied by each device as well as differences between both devices. In this section a comparison is made between the moduli predictions using Dynaflect and FWD testing system. The layer moduli obtained from the plate loading tests on some of the test sections will also be compared with the dyna mic NDT devices. Table 6.15 Comparison Between Tuned Layer Moduli and Applied FWD Load Test Mile Post Load Load Layer Moduli (ksi) Road Number Deflection Response (kips) Ei E2 E3 E4 4.760 338.3 46.0 45.0 41.5 SR 24 11.112 linear 7.176 338.3 55.0 45.0 37.5 8.816 338.3 55.0 40.0 38.6 4.696 315.0 35.0 25.0 18.0 SR 12 1.485 quasi- 6.920 400.0 35.0 22.0 21.0 linear 9.232 400.0 31.0 20.0 18.5 9.288 400.0 31.0 20.0 17.4 non!inear 4.656 360.0 110.0 35.0 25.0 SR 26B 11.205 (stress softening) 6.880 9.096 360.0 360.0 110.0 90.0 40.0 45.0 11.5 11.0 9.112 360.0 120.0 50.0 11.0 nonlinear 4.656 200.0 71.0 57.0 9.0 SR 15A 6.551 (stress- 7.008 200.0 55.0 50.0 6.9 stiffening) 9.026 200.0 50.0 42.0 7.2 nonlinear 4.513 90.5 75.0 60.0 11.5 SR 15B 4.811 (stress- 6.769 90.5 60.0 50.0 9.6 stiffening) 8.962 90.5 52.8 50.0 10.2 238 6.6.1 Comparison of Deflection Basins Figures 6.50 through 6.63 show comparisons of the field measured FWD and Dynaflect deflection basin for each test section. The deflec tions are normalized to an equivalent 1000-lb. load level. Deflection basins normalized with respect to a standard load level are very helpful in comparing NDT devices that apply different loads to the pavement. Normalization of the FWD deflection basins, as illustrated in the plots, is also another way of assessing linearity and stress dependency of the load-deflection response. The figures indicate that FWD deflections measured at about 7.0 kips load levels are very close to those measured around 9.0 kips for all test sections. This would suggest that line arity is achieved at FWD loads beyond 6.0 kips as postulated in Section 6.5.5. In comparing the Dynaflect deflection basin to the FWD deflection basins for each test section, the following three trends can be differ entiated from the normalized plots: 1. Pavements which have FWD deflections greater than the Dynaflect deflections. Test sections in this group are SR 26C, US 301, US 441, and SR 12. The normalized plots for these pavement sections are illustrated in Figures 6.50 to 6.53. 2. Pavements which exhibit the reverse of the above, that is, Dynaflect deflections are greater than those of the FWD. These are SR 26B, SR 15A, and SR 715 test sites and they are shown in Figures 6.54, 6.55, and 6.56, respectively. Note that the SR 715 site (Figure 6.56) had similar FWD normalized deflection basins, confirming the linear load response diagram of Figure 6.9. The different Dynaflect deflection basin could therefore be due to differences in NDT devices. NORMALIZED DEFLECTION (mils) 239 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.50 Comparison of Measured NDT Deflection Basins on SR 26C M.P. 10.166 NORMALIZED DEFLECTION (mils) 240 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.51 Comparison of Measured NDT Deflection Basins on US 301 M.P. 21.585 NORMALIZED DEFLECTION (mils) 241 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.52 Comparison of Measured NDT Deflection Basins on US 441 M.P. 1.237 NORMALIZED DEFLECTION (mils) 242 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.53 Comparison of Measured NDT Deflection Basins on SR 12 M.P. 1.485 NORMALIZED DEFLECTION (mils) 243 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.54 Comparison of Measured NDT Deflection Basins on SR 26B M.P. 11.205 NORMALIZED DEFLECTION (mils) 244 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.55 Comparison of Measured NDT Deflection Basins on SR 15A M.P. 6.549 NORMALIZED DEFLECTION (mils) 245 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.56 Comparison of Measured NDT Deflection Basins on SR 715 M.P. 4.722 NORMALIZED DEFLECTION (mils) 246 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.57 Comparison of Measured NDT Deflection Basins on SR 26A M.P. 11.912 NORMALIZED DEFLECTION (mils) 247 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.58 Comparison of Measured NDT Deflection Basins on SR 24 M.P. 11.112 NORMALIZED DEFLECTION (mils) 248 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.59 Comparison of Measured NDT Deflection Basins on I-10A-- M.P. 14.062 NORMALIZED DEFLECTION (mils) 249 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.60 Comparison of Measured NDT Deflection Basins on I-10B M.P. 2.703 NORMALIZED DEFLECTION (mils) 250 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.61 Comparison of Measured NDT Deflection Basins on I-10C-- M.P. 32.071 NORMALIZED DEFLECTION (mils) 251 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.62 Comparison of Measured NOT Deflection Basins on SR 15B M.P. 4.811 NORMALIZED DEFLECTION (mils) 252 RADIAL DISTANCE FROM CENTER OF LOADED AREA (in.) Figure 6.63 Comparison of Measured NDT Deflection Basins on SR 15C M.P. 0.055 253 3. Those pavement sections in which FWD and Dynaflect deflection basins are similar, especially when the higher FWD load deflections are used in the comparison. Figures 6.57 through 6.63 show that test pavements SR 26A, SR 24, I-10A, I-10B, I-10C, SR 15B, and SR 15C fall into this group. It must be emphasized that similarity used here implies that deflection basins from the Dynaflect and the FWD are either close to each other or cross over (overlap). A typical example of the latter is SR 15C. Thus group 3 is an overlap between groups 1 and 2. The differences between the Dynaflect and FWD deflection basins from the normalized plots suggest that response of the pavements is affected by type of NDT device and loading mode. The resultant effect on the moduli required to model the pavements is discussed in the next section. 6.6.2 Comparison of Layer Moduli The tuned layer moduli obtained from modeling of the Dynaflect and FWD deflection basins are compared below. The comparison here applies to only the highest (9-kip) FWD deflections. However, Section 6.5.5 had shown that the effects of nonlinearity and stress dependency in FWD load-deflection response is reduced considerably at FWD loads greater than 6.0 kips. Also the use of the 9 kips FWD load response charac teristics approximates the rear-axle loading of an 18-kip single axle design load. Plate loading test results listed in Table 5.3 are also compared here with the NDT moduli predictions for those pavement sec tions in which tests were performed. Tables 6.16 through 6.19 compare moduli from the Dynaflect and FWD deflections for the asphalt concrete, base course, subbase, and subgrade 254 Table 6.16 Comparison of the Asphalt Concrete Modulus for the Test Sections Test Road Mile Post Number S (in.) Mean Temperature (F) AC Modulus, Ex (ksi) Rheology Dynaf1ect FWD SR 26A 11.912 8.0 81 171.3 171.5 171.5 SR 26B 11.205 8.0 59 406.5 360.0 360.0 SR 26C 10.168 6.5 82 171.3 171.5 171.5 SR 24 11.112 2.5 57 338.3 338.3 338.3 US 301 21.580 4.5 69 256.6 250.0 250.0 US 441 1.236 3.0 79 289.6 290.0 290.0 I-10A 14.062 8.0 104 60.8 65.0 100.0* I-10B 2.703 7.0 88 113.2 113.0 100.0 I-10C 32.071 5.5 106 66.9 67.0 120.0* SR 15B 4.811 7.0 127 90.5 150.0* 90.5 SR 15A 6.546 8.5 120 85.0 150.0* 150.0* SR 715 4.722 4.5 111 92.6 92.6 92.6 SR 715 4.720 4.5 111 92.6 92.6 92.6 SR 15A 6.546 8.5 120 85.0 85.0 85.0 SR 12 1.485 1.5 102 400.0 400.0 SR 15C 0.055 6.75 105 80.3 80.0 80.0 SR 15C 0.065 6.75 105 80.3 150.0 150.0 * Significant differences between E1 predicted from rheology of recovered asphalt and Dynaflect or FWD E1 values. 255 layers, respectively. In Table 6.16, the modulus of the asphalt con crete determined from rheology test data (Table 6.5) are also listed for comparison purposes. The table shows favorable agreement between the NDT moduli and the indirect method of using low-temperature viscosity relationship. Slight differences occur at SR 26B in which the rheology moduli prediction was reduced by about 12 percent in tuning the NDT deflection basins. In some test sections where there were differences, it was found that the Dynaflect moduli matched the rheology value while the FWD required some adjustment in the E2 or vice versa. These always occurred with pavements tested at higher temperatures (90F or more). It is generally believed that the indirect method of estimating Ex works best at mean pavement temperatures less than 80F or where E is greater than 100 ksi. The NDT Zl values listed in Table 6.16 were correlated to the respective mean pavement temperatures to establish a simple and rapid method of estimating E: values for routine applications. The resulting relationship is shown in Figure 6.64. The asphalt concrete modulus, E , of pavements with no visible cracks can be determined from the mean pavement temperature, T, using the following equation Log Ex = 6.4147 0.0148 T Eqn. 6.3 In Equation 6.3, Ex is in psi, and T is in F, as illustrated in Figure 6.64. The relationship for considerable cracking in Figure 6.64 can be used when pavement cracks are spaced sufficiently to eliminate their influence on the NDT deflections. This would apply to pavement sections that have uncracked segments within cracked segments. However, if the RESILIENT MODULUS, E., (psi) 256 Figure 6.64 Relationship Between Asphalt Concrete Modulus, E1, and Mean Pavement Temperature 257 pavement exhibits extensive cracking (e.g., alligator cracking), Ex will be reduced considerably. Details pertaining to the use of Figure 6.64 will be presented in Chapter 8. Tables 6.17 and 6.18 show that the base course and subbase moduli from the Dynaflect are, respectively, higher than those for the FWD. The corresponding comparison for the subgrade is shown in Table 6.19 and this does not necessarily follow the trend of the base and subbase layers. A comparison for all three layer moduli is shown in Figure 6.65 and Table 6.20. In Table 6.20, the ratio of the Dynaflect to FWD moduli for all test sections are listed for the various layers. The good agreement for the AC layer has already been discussed. For the base course layer, the ratio ranges from 1.0 to 3.87. The 3.87 value oc curred with the SR 12 test section in which the base course material was a sand-clay mixture instead of the limerock material used for the rest of the test pavements. The higher predictions of E2 from the Dynaflect than FWD agrees with the findings of Bush and Alexander (23), and Wise man et al. (130). These researchers found that the moduli of the base course determined from FWD deflection basins were significantly lower than those obtained from analyzing deflection basins produced by either the Dynaflect, Road Rater, Pavement Profiler, or 16-kip vibrator. The Pavement Profiler and 16-kip vibrator also operate on the steady-state vibratory loading principles of the Dynaflect and Road Rater. The base course moduli predictions obtained from this research therefore support the belief that deflection basins produced by steady-state vibratory loading devices result in higher base course moduli than those produced by impulse loading devices such as the FWD. 258 Table 6.17 Comparison of the Base Course Modulus for the Test Sections Test Road Mile Post Base Course Modulus, E (ksi) Number Dynaflect FWD PLT SR 26A 11.912 105.0 75.0 SR 26B 11.205 90.0 90.0 SR 26C 10.168 55.0 45.0 SR 24 11.112 105.0 75.0 US 301 21.580 120.0 45.0 56.0 US 441 1.236 85.0 55.0 40.3 I-10A 14.062 95.0 90.3 93.8 I-10B 2.703 80.0 60.0 80.1 I-10C 32.071 105.0 85.0 66.5 SR 15B 4.811 120.0 52.8 SR 15A 6.549 120.0 95.0 SR 715 4.722 75.0 45.0 SR 715 4.720 65.0 65.0 SR 12 1.485 120.0 31.0 43.4 SR 15C 0.055 105.0 35.0 SR 15C 0.065 105.0 50.0 SR 15A 6.546 85.0 45.0 __ 259 Table 6.18 Comparison of the Subbase Modulus for the Test Sections Test Road Mile Post Subbase Modulus, E3 (ksi) Number Dynaflect FWD PLT SR 26A 11.912 70.0 45.0 SR 26B 11.205 60.0 45.0 -- SR 26C 10.168 35.0 27.5 SR 24 11.112 75.0 40.0 -- US 301 21.580 60.0 35.0 27.8 US 441 1.236 60.0 35.0 29.7 I-10A 14.062 89.4 80.0 I-10B 2.703 65.0 50.0 I-10C 32.071 85.0 50.0 44.6 SR 15B 4.811 75.0 50.0 SR 15A 6.549 40.0 39.5 SR 15A 6.546 65.0 35.0 SR 715 4.722 50.0 25.0 SR 715 4.720 45.0 26.0 -- SR 12 1.485 75.0 20.0 46.10 SR 15C 0.055 75.0 12.0 SR 15C 0.065 75.0 44.0 260 Table 6 .19 Comparison of the Subgrade Modulus for the Test Sections Test Road Mile Post Subgrade Modulus Number Dynaflect FWD PLT SR 26A 11.912 14.6 18.7 SR 26B 11.205 7.9 11.0 SR 26C 10.168 28.5 25.5 SR 24 11.112 38.6 38.6 US 301 21.580 38.6 25.0 11.6 US 441 1.236 27.5 20.0 11.6 I-10A 14.062 105.0 130.0 32.8 I-10B 2.703 60.0 43.0 21.2 I-10C 32.071 40.0 46.0 29.7 SR 15B 4.811 8.1 10.2 SR 15A 6.549 4.8 7.5 SR 15A 6.546 5.0 7.0 SR 715 4.722 6.0 11.0 SR 715 4.720 5.5 10.5 -- SR 12 1.485 26.5 18.5 15.4 SR 15C 0.055 5.5 9.8 SR 15C 0.065 5.5 10.0 DYNAFLECT (1-KIP LOAD) MODULUS (KSI) Figure 6.65 Comparison of Dynaflect and FWD Tuned Layer Moduli 262 Table 6 .20 Ratios of Dynaflect Moduli to FWD Moduli for Test Sections Test Road Mile Post Number E(DYN)/E(FWD) AC Base Subbase Subgrade SR 26A 11.912 1.00 1.40 1.56 0.78 SR 26B 11.205 1.00 1.00 1.33 0.72 SR 26C 10.168 1.00 1.22 1.27 1.12 SR 24 11.112 1.00 1.40 1.88 1.00 US 301 21.580 1.00 2.67 1.71 1.54 US 441 1.236 1.00 1.55 1.71 1.38 I-10A 14.062 0.65 1.05 1.12 0.81 I-10B 2.703 1.13 1.33 1.30 1.40 I-10C 32.071 0.56 1.24 1.70 0.87 SR 15B 4.811 1.66 2.27 1.50 0.79 SR 15A 6.549 1.00 1.26 1.01 0.64 SR 15A 6.546 1.00 1.89 1.86 0.71 SR 715 4.722 1.00 1.67 2.00 0.55 SR 715 4.720 1.00 1.00 1.73 0.52 SR 12 1.485 1.00 3.87 3.75 1.43 SR 15C 0.055 1.00 3.00 6.25 0.56 SR 15C 0.065 1.00 2.10 1.70 0.55 263 Correlation of the base course modulus (E2) from the Dynaflect and FWD for the various test sections resulted to the following equation: E2 (Dynaflect) = 1.380 E2 (FWD) Eqn. 6.4 (R2 = 0.871, N = 17) Table 6.20 shows that the ratio of the subbase modulus from the Dynaflect to the FWD ranges from 1.01 to 3.75, except for SR 15C M.P. 0.055 in which a ratio of 6.25 was obtained. This value was considered to be an outlier (though both deflection basins tuned well) in subse quent analysis. The trend for the subbase is similar to that of the base course. Therefore, the same conclusions, with regard to the effect of the type of NDT device on granular base course materials, applies to the subbase layer. Regression analysis of Dynaflect and FWD data in Table 6.18 resulted in the following equation: E3 (Dynaflect) = 1.488 E$ (FWD) Eqn. 6.5 (R2 = 0.930, N = 16) It is interesting to note that not only does the R2 value increase, but also the regression coefficient increased in Equation 6.5 compared to Equation 6.4. Thus, higher ratios (see Table 6.20) were obtained for the subbase than the base course. The comparison between Dynaflect and FWD predictions of the sub grade modulus (E^) is presented in Tables 6.19 and 6.20. The ratio 264 of the Dynaflect to FWD E4 values ranges from 0.55 to 1.54. In only 6 out of 17 cases did the Dynaflect predict higher E4 values than the FWD. Some researchers argue that the light loading produced by the Dynaflect would result in higher modulus values than the moduli obtained with the heavy loads used in the FWD. The findings from this study tend to contradict this argument in the case of the subgrade layer. Also, this is the only layer which has unique relationship between the modulus and the farthest sensor deflection(s) for each NDT device. The subgrade modulus comparison does not indicate any effect of nonlinearity in the subgrade soil materials. Therefore, the differences in the moduli pre dictions could be attributed to the inherent differences between the two NDT devices; viz, vibratory loading in the Dynaflect versus impulse loading in the FWD. Regression analysis of Dynaflect E4 values to FWD E4 values resulted in the following equation: E4 (Dynaflect) = 0.933 E4 (FWD) Eqn. 6.6 (R2 = 0.929, N = 17) Tables 6.17 to 6.19 illustrate the comparison of the moduli ob tained from plate loading tests and the NDT devices for the base, sub base, and subgrade layers, respectively. Tables 6.17 and 6.18 indicate that the plate bearing E2 and E3 values are closer to the FWD than the Dynaflect predictions. This seems to support the argument that FWD deflection response is influenced by the rigid plate effects. For example, I-10A which was very stiff produced similar E2 values using the 265 Dynaflect, FWD, and plate loading tests. Further research is required to study the possible effects of the rigid FWD plate in interpreting load-deflection response. Table 6.19 shows that the subgrade moduli obtained from the plate loading test were generally lower than those from the NDT devices. For SR 12, the FWD and plate loading E^ values compare well. However, for I-10A test site, which had very stiff layers, the plate bearing test prediction of E4 was too low compared to the Dynaflect and FWD predic tions. The poor prediction of the subgrade modulus from the plate load tests is attributed to possible disturbance during trenching, measure ment of plastic (or non-recoverable) deformation during testing, and the static loading conditions used in the plate test as compared to the dynamic NDT tests. 6.7 Analyses of Tuned NDT Data 6.7.1 General Section 6.5 presented the modeling of the Dynaflect and FWD deflec tions for the various test sections. The resultant moduli from modeling have been referred to as tuned moduli for the respective NDT devices. This section analyzes the moduli and corresponding BISAR predicted deflections in the hope of developing simplified layer moduli prediction equations, especially for the Dynaflect testing system. The predicted deflections are used in this analysis because they matched (approxi mately) the field measured values and more importantly meet the assump tions inherent with the use of multilayered elastic theory. Details pertaining to the analyses are presented for the Dynaflect and FWD in Sections 6.7.2 and 6.7.3, respectively. 266 6.7.2 Analysis of Dynaflect Tuned Data 6.7.2.1 Comparison of Measured and Predicted Deflections. It was mentioned in Section 6.5.2 that the measured and predicted Dynaflect deflections (Figures 6.15 to 6.31) were generally in good agreement for the test pavement sections. The measured and predicted deflections listed in Tables 6.1 and 6.8, respectively, were regressed to evaluate the reliability of the BISAR predicted Dynaflect deflections. The regression analyses utilized only sensors 1, 4, 7, and 10 deflections. These were the sensor deflections selected from the theoretical analysis (Chapter 4) to be related to the moduli of specific layers. Figures 6,66, 6.67, 6.68 and 6.69 present the relationship between BISAR predicted and field measured Dynaflect deflections at modified sensor locations 1, 4, 7, and 10, respectively. In all cases, the high R2 value (R2 > 0.96) indicated an expectionally good correlation between predicted and measured deflections. The regression equations for D^ and Dy (Figures 6.67 and 6.68) provided an almost perfect correlation with the intercept and slope being within 0.015 mils of zero and 0.018 mils of unity, respectively. The Dx values (Figure 6.66) tended to yield a slightly higher intercept (0.065) and slope (1.107) which results in the predicted deflections being slightly greater than those measured. There were four test sites where predicted Dx values were about 0.2 to 0.3 mils greater than the measured D1 values. This difference may be due to sensor placement variation, the use of single Dx measurement in the earlier tests, variation in measured Dx response according to wheel positioning, or where complete tuning was not achieved (e.g., SR 24 and SR 12). PREDICTED D! (mils) 267 0 0.5 1.0 1.5 2.0 2.5 3.0 MEASURED D1 (mils) Figure 6.66 Relationship Between Predicted and Measured Dynaflect Modified Sensor 1 Deflections PREDICTED D4 (mils) 268 Figure 6.67 Relationship Between Predicted and Measured Dynaflect Modified Sensor 4 Deflections PREDICTED Dy (mils) 269 Figure 6.68 Relationship Between Predicted and Measured Dynaflect Modified Sensor 7 Deflections PREDICTED D1 0 (mils) 270 Figure 6.69 Relationship Between Predicted and Measured Dynaflect Modified Sensor 10 Deflections 271 Other than one test site (SR 80 Section 2), the D10 values pro vided an excellent, highly reliable relationship (Figure 6.69). How ever, the slope of 0.95 suggests that predicted deflections are about 5 percent less than measured 01Q values. The discrepancy occurs because the straight line log-log relationship for predicting E4 from D1() (stan dard D5) tends to be a curvilinear (hyperbolic) relationship for E4 values below 10.0 ksi or above 100.0 ksi (see Figure 2.8). 6.7.2.2 Development of Simplified Layer Moduli Equations. Si nee / the tuned layer moduli provided predicted Dynaflect deflections which correlated exceedingly well with the measured deflections, regression analyses were performed to assess the relationship between a) Composite modulus of asphalt concrete and base course layers (E12) and Dj D4 b) Subbase or stabilized subgrade modulus (Eg) and D4 D? c) Subgrade modulus (E4) and D1Q. As mentioned previously, these sensor deflections were selected from the analytical study on the basis of being related to the moduli of specific layers. It was necessary to combine the asphalt concrete and base course moduli because the analyses had indicated that no sensor location or combination of sensor deflections were suitable for separation of Ex and E2. The series of equations (Equation 4.1 through 4.10) developed for prediction of either Ej or E2 from D1 D4, with a reasonable esti mate of E2 or E respectively, albeit their high degree of prediction accuracy, were considered to be too complex for routine evaluation of pavements. Therefore, it was necessary to simplify the various £1 and E2 prediction equations. The approach used is described below. 272 It was shown in Figures 4.14 to 4.19 that Dx in the modified Dynaflect sensor array system was dependent only on the surface and base course layers. Thus, Dx d4 = fn (Ej, tlf E2, t2) = Eeq or E12 Eqn. 6.7 where Dx 04 is the difference in modified Dynaflect sensor deflections (see Figure 4.2), Ej is modulus of the asphalt concrete layer, E2 is modulus of the base course layer, tx is the thickness of the asphalt concrete layer, t2 is the thickness of the base course layer, and E12 (or Eeq) is a composite (or an equivalent) asphalt concrete and base course modulus. Two equations were employed to combine the surface and base course layer stiffnesses into a composite E12 value. The first formula is essentially a weighted average formula, and is of the form E t + E t E = '1 22- Eqn. 6.8 12 t + t 1 2 Equation 6.8, which is a commonly-used weighting formula, has pre viously been utilized by Vaswani (124) to combine pavement layers over the subgrade. The second method used to combine E and E2 follows the approximation suggested by Thenn de Barros (115). The equation is of the form 273 E 12 + t 3 ST 2 Eqn. 6.9 2 Figures 6.70 and 6.71 present the relationships between E and Dx D4 for each of the weighting methods. There is very little difference between modulus-deflection relationship for the standard weighting method (Equation 6.8) and the Thenn de Barros1 formula (Equation 6.9), as shown in Figure 6.70 and Figure 6.71, respectively. It would appear that either method would be suitable for defining E12 although the difference between methods becomes significant at low E values and high Dx D4 values (e.g., E12 < 34.0 ksi, and D1 D4 > 1.0 mil). Thus knowing E from Dj D^, and Ej from asphalt rheology (or using Figure 6.64), E2 can be calculated using Equations 6.8 and 6.9. A procedure incorporating the above and other layer moduli predictions for routine pavement evaluation studies is presented in Appendix F. The relationship between E3 and 04 D? is illustrated in Figure 6.72. The figure shows that the simplified format of Equation 4.15 could be used for a wider range of E3 values. Even though the results of the regression analysis of Figure 6.72 is fairly good, the range in E3 values is still narrow and limited to only two values below 20.0 ksi. Additional test data in the lower range would be helpful in either verifying the validity of the E3 prediction equation or modifying the regression equation. Subgrade modulus prediction equations and the modified Dynaflect sensor 10 deflection values are shown in Figure 6.73. The simplified equation (Equation 4.35), as previously explained, was originally developed using data collected in Quebec, Canada and Florida. Figure COMPOSITE MODULUS, E12 (ksi) 274 D1 D4 (mils) Figure 6.70 Relationship Between E12 (Using Equation 6.8) and Dx - COMPOSITE MODULUS, E1 2 (ksi) 275 - D4 (mils) Figure 6.71 Relationship Between E12 (Using Equation 6.9) and Dx D4 276 D4 D? (mils) Figure 6.72 Relationship Between E3 and D4 D? SUBGRADE MODULUS, E4 (ksi) 277 DYNAFLECT MODIFIED SENSOR DEFLECTION, D ^ 0 (mils) Figure 6.73 Relationship Between and D1(J 278 6.73 therefore compares the relationship- between the results from that study and those obtained from the test pavement sections used in this study. From a practical standpoint, there is very little difference between the E4 prediction equations. This difference is not significant enough to warrant the use of one equation in preference to the other, except when D10 is less than 0.06 mils or much greater than 1.0 mil. It was shown in Section 4.4.1.4 that the use of the simplified E4 predic tion equation result in the overprediction of weak subgrades (E4 < 10.0 ksi) and underprediction of high or stiff subgrades (E4 > 100.0 ksi). The results obtained with the use of the modified Dynaflect system indicate that separation of loaded areas produces double bending which allows for the optimal placement of sensors to separate the response of the different pavement layers. This somewhat unique load-sensor config uration makes it possible to develop simplified (power law) equations for prediction of layer moduli. If desired, the predicted layer moduli can be used as "seed moduli" in iterative elastic multi-layer computer programs (e.g., BISDEF). This would help to ensure that unique solutions are obtained. It has been demonstrated in Section 6.5 that predicted Ex and E4 values are reliable and seldom require much adjust ment or tuning to match the measured deflection basin. Therefore, it appears that the most desirable approach in computer simulation is to use E2 and E3 values as "seed moduli" for any iterative or judgment modified analysis. Appendix F describes a recommended testing and analysis procedures using the modified Dynaflect testing system. The positions of the five geophones in the conventional system were modified into the form shown in Figure F.l. The computational algorithms of the recommended 279 procedure in Appendix F have been incorporated into the BISAR elastic layer computer program to perform the iteration after the initial computation of the "seed moduli." Figure 6.74 shows a simplified flow chart of the modified BISAR program utilizing the modified Dynaflect testing system. The modified program is referred to as DELMAPS1 which is an acronym for Dynaflect Evaluation of _Layer Moduli for Asphalt _Pavement Systems Version l_. The iteration part of the program is interactive and user-specified with respect to the modulus value to be adjusted to achieve the desired tuning. A partial listing of the DELMAPS1 program is presented in Appendix G. 6.7.3 Analysis of FWD Tuned Data 6.7.3.1 Comparison of Measured and Predicted Deflections. It was explained in Section 6.5.3 that tuning of the FWD deflection basins was extremely difficult for most of the test pavements. It was relatively easy to match D. and D. or D_, and generally difficult to simulate the intermediate sensor deflections. This is demonstrated in Table 6.21 in which correlation between measured and predicted FWD deflections is presented. The R2 values are generally good for the first two and last two sensors, and poor for sensors 3, 4, and 5 deflections. Also, sensors 3, 4 and 5 have slopes lower than unity in their regression equations. Comparison between BISAR predicted and field measured FWD deflections indicated that percent errors as high as +35 percent were obtained at sensor positions 3, 4, and 5. However, the difference in deflections at sensors 1, 2, 6, and 7 were generally of the order of +10 percent. 280 Figure 6.74 Simplified Flow Chart of DELMAPS1 Program 281 Table 6.21 Correlation Between Measured and Predicted FWD (9-kip Load) Deflections Sensor N R2 Regression Equation 1 18 0.993 D i P = -0.683 + 1.025 DlM 2 18 0.964 D2p = 0.385 + 1.005 D2M 3 18 0.914 3P = 1.239 + *947 D3M 4 18 0.873 4P = 0.822 + 0.925 D4M 5 18 0.933 5P = 0.453 + *915 D5M 6 18 0.983 6p 0.090 + 0.955 D6jv| 7 18 0.993 7P = -0.032 + 1.010 D7M The relatively high R2 values for sensors 1, 2, 6, and 7 indicates good prediction accuracy for E1 and E4 values as compared to E2 and E3. Generally, the E4 value contributes about 60 percent to the entire deflection basin depending on the stiffness of the pavement structure. Therefore, if the intermediate and last sensor deflections had been matched, lower deflections would probably have been measured at Dx and D2 due to the influence of rigid plate effects in the FWD system which is modeled as a flexible plate in elastic layer programs. An attempt was made to demonstrate this effect using a rigid plate loading approxi mation in the elastic layer program which would produce the same deflec tion as measured with the FWD. Although, this technique has previously been employed by Roque (96), it was found to be too cumbersome to pursue. Nevertheless, the rigid plate appears to influence FWD load- deflection response. It is also believed that the FWD load-geophone 282 configuration does not provide separation of the layers' response as was obtained with the Dynaflect. A modified FWD system utilizing a dual loading system appears worth pursuing in future NDT research. 6.7.3.2 Development of Prediction Equations. Although tuning of the FWD deflection basins was not as good as that of the Dynaflect, the tuned data were used to develop new equations in the hope of improving those presented in Section 4.3.3. The FWD prediction equations pre sented in this section and that of Section 4.3.3 may be used for the prediction of the initial or "seed" moduli for subsequent use in itera tive elastic multilayered computer programs. The range of layer moduli and thicknesses are as follows: 80.0 < Ex < 400.0 ksi and 1.5 < tx < 8.5 in. 31.0 < E2 < 95.0 ksi and 6.0 < t < 24.0 in. 12.0 < E3 < 80.0 ksi and 12.0 < t3 < 17.0 in. 7.0 < E4 < 130.0 ksi and t, = semi-infinite. 4 The corresponding range of deflections (9-kip FWD load) as listed in Table 6.11 are: 3.58 < D < 29.54 mils 3.51 < D2 < 17.81 mils 2.16 < D3 < 14.67 mils 1.16 < D, < 11.03 mils 0.65 < 05 < 8.80 mils 0.41 < D. < 6.99 mils 6 0.31 < D? < 5.56 mils The range of parameters listed above are slightly different from those used in the theoretical analysis. The subbase and subgrade moduli ranges are increased here. Also, the base course thickness is increased 283 from the 8.0 in. used in the theoretical study to a high value of 24.0 in. (SR 715). Since these values represent actual test pavements, the resultant prediction equations would be more reliable than those of Section 4.3.3, unless of course their prediction accuracies are lower. 6.7.3.2.1 Asphalt concrete modulus, Ex Multiple linear regression analysis of the test data resulted in the following equation: log E1 = 3.229 1.0683 log {tj 2.8217 log (D1 D2) + 1.008 log (Dx D3) + 0.8835 log (D1 05) Eqn. 6.10 (R2 = 0.885 and N = 22) Error analysis indicated that 5 out of 22 pavements had pre dictions with errors greater than 20 percent with one pavement having as high as 44 percent prediction error. This pavement was SR 12 which had an asphalt concrete thickness of 1.5 in. As explained in Section 4.4.3, the SR 12 pavement was deleted from the data base and the remaining data analyzed to obtain Equation 6.11. log Ej = 2.215 0.2481 log (tj 12.445 log (Dx D2) + 17.205 log (Dx D3) 5.871 log (Dx DJ Eqn. 6.11 (R2 = 0.959 and N = 21) 284 This equation is similar to Equation 4.20 except that the regression coefficients and range of parameters applicable are different. Two pavements had prediction errors of -21.8 and 16.8 percent. These were SR 24 and US 301, with asphalt concrete thick nesses of 2.5 and 4.5 in., respectively. All other pavements had E: predictions of the order of 10 percent error. Therefore, Equa tion 6.11 may be preferred over Equations 4.19 and 4.20, since it covers a broader range of variables and also developed from tuned test data. 6.7.3.2.2 Base course modulus, E2 Analysis of the tuned data using E2 as the dependent variable resulted to an equation similar to Equation 4.21 which was obtained from the theoretical analysis. log E2 = 3.280 0.03326(t ) 0.1179 log (D?) + 3.3562 log (Dx 0 ) 9.0167 log (D1 DJ - 4.8423 log (Dj Dg) Eqn. 6.12 (R2 = 0.959 and N = 22) Error analysis indicated that only two pavements (SR 15A M.P. 6.549 and 6.546) had -15.6 and 15.8 percent prediction errors. Prediction errors for the others were 10 percent or less. Equation 6.12 should be used in place of Equation 4.21 unless the applicable range of the former is excessively exceeded. 6.7.3.2.3 Stabilized subgrade modulus, E Multiple regres sion analysis of the data set resulted in the following equation 285 log E, = 4.970 + 0.1773(t.) 1.6966 log(t) 0.1069(DJ O i 1 H + 0.2552(D7) 2.6546 1og(D1) 3.9906 log(D3) + 1.8241 log(Dc) + 3.5092 log(D0 D_) b o Eqn. 6.13 R2 = 0.887 and N = 22 Error analysis indicated that one pavement (SR 15B) had -34.6 percent prediction error. The actual Eg value was 50.0 ksi, while the predicted value was 32.7 ksi. Others had prediction errors generally less than +15 percent. Equation 6.13 for the prediction of Eg applies to a slightly wider range of variables than Equation 4.24 which was selected from the theoretical analysis. However, the latter is more simplified and contains fewer variables than Equation 6.13. Also, since the R2 value is greater, Equation 4.24 should be used for E3 predic tions. 6.7.3.2.4 Subgrade modulus, E Regression analyses of E^ against either Dg, or Dy, or both resulted in the following equa tions : E = 53.697(0 )"i.04i Eqn. 6>14 4 6 (R2 = 0.997 and N = 22) E = 39.690(D )1.004 Eqn< 6>15 (R2 = 0.999 and N = 22) 286 E = 39.427(D )*023(D p-026 Eqn. 6.16 4 6 7 (R2 = 0.999 and N = 22) The percent prediction errors of Equations 6.14 to 6.16 were generally below +10 percent. The maximum prediction error of Equa tion 6.14 was 7.0 percent while the other two had 9.0 percent pre diction errors. However, Equations 6.15 and 6.16 had greater pre diction accuracy than Equation 6.14, with prediction errors gener ally less than +4 percent. The relationship between E^ and Dg or D? is illustrated in Figure 6.75. The corresponding equations (Equations 6.14 and 6.15) apply to a wider range of E4 values than those obtained from the theoretical analysis. Also, the slopes of Equations 6.14 and 6.15 are close to unity, approaching the format of the Dynaflect simpli fied E^ prediction equation. It was initially believed (in Section 4.4.2.4) that the use of Equations 4.28 or 6.16, which incorporate two sensor deflections, should generally minimize the potential for prediction error due to measurement variablity. However, it was found that variation in D. 6 as high as 100 percent would have about one percent change in the predicted E^ value with the use of Equation 6.16. Thus, Equation 6.16 is not very sensitive to changes in D. as compared to that of O D?. Therefore, Equations 6.14 and 6.15 (Figure 6.75) should be used for E4 predictions, and whenever possible, an average value should be used. Where surface cracks exist, one of the equations might be preferable to the other depending on the ability of the pavement to transfer loads to the geophone locations. SUBGRADE MODULUS, E4 (ksi) 287 FWD (9 kips load) SENSOR DEFLECTION, D6 or j (mils) Figure 6.75 Relationship Between and FWD Dg and D? CHAPTER 7 INTERPRETATION OF IN SITU PENETRATION TESTS 7.1 General The testing program for the penetration tests (CPT and DMT) has been presented in Chapter 5. The electric cone penetration test, with the computerized data acquisition system, yielded cone resistance (qc), local friction (fs), and their ratio FR = fs/qc (called the friction ratio) values for the various depths of penetration. The plots of these profiles, using the HP 7470A graphics plotter, are presented in Appendix C for each pavement section. The dilatometer test consisted of two basic readings which are, 1) the gas pressure required to lift the membrane off its seating, and 2) the pressure to deflect the center of the membrane 1.1 mm. From these two readings and two initial calibration readings, three dilato meter parameters Ig (Material Index), Kg (Horizontal Stress Index), and Eg (Dilatometer Modulus) are calculated. A number of useful empirical and experimental correlations between these parameters and important geotechnical parameters have been developed by Marchetti (68). This allows a comprehensive characterization of the penetrated deposit. Using the data reduction program described by Marchetti and Crapps (69), the DMT results were reduced and presented in Appendix D. This chapter presents an analysis of the penetration tests con ducted on the pavement sections. The feasibility of determining the modulus of the pavement layers and underlying subgrade soils from the 288 289 penetration tests are assessed. Also, the effects of the subgrade stratigraphy on the NDT deflection basins are evaluated. 7.2 Soil Profiling and Identification Based upon continuous monitoring of cone penetration tests on various soils, many attempts have been made by engineers to develop classification charts relating the soil type to the measured cone pene tration parameters. Among those is the classification chart based on qc and FR developed by Robertson and Campanella (95). Similarly, an iden tification chart for soil type using Ig and Kg from dilatometer tests has been developed by Marchetti (68). Both procedures were used to identify the stratigraphy of the test pavement sites, especially for the \ underlying subgrade soils. There was good agreement between the two penetration tests in providing delineation between sandy and clayey/ silty soils. However, the DMT could not identify sand-clay mixes which were interpolated from the CPT identification charts. Because the para meter Ig increases continuously with grain size, Marchetti's correlation cannot identify a sand-clay mixture (29). Even though no detailed labo ratory classification tests were conducted, these results were used in subsequent analysis of the penetration tests. The accuracy and repeatability of the test soundings were evaluated from the multiple tests performed on each site. Figure 7.1 shows, for example, the variation of qc and FR with depth for SR 12. For the same test pavement the variation of Eg and Kg with depth is also shown in Figure 7.2. These plots indicate the reproducibility of the penetration tests considering spatial soil variability. The CPT and DMT profiles seemed to agree with the variability of the test sites as inferred from CONE TIP RESISTANCE, Cfc (MPa) FRICTION RATIO (%) ro o Figure 7.1 Variation of qc and FR with Depth on SR 12 DI L ATOM ETER MODULUS, ED (MPa) HORIZONTAL STRESS INDEX, KD Figure 7.2 Variation of Eg and Kg with Depth on SR 12 292 the deflections measured by the nondestructive tests for all test pave ments. The variability in the subgrade or foundation soils is also illus trated by the CPT and DMT logs in Figures 7.3 through 7.7 for some of the test pavements. There was a general tendency for the strength and modulus of the subgrade to decrease significantly to a depth of about 2.0 m. The qc and Eq profiles, as illustrated in Figures 7.1 through 7.7, can also be used to evaluate the structural condition of a pave ment. These profiles of stiffness would assist the engineer in iden tifying possible zones of weakness in the pavement or subgrade. Figure 7.3 shows, for example, that a weak (soft) layer exists at a depth of 2.0 m in the subgrade for SR 26A. Figure 7.4 also suggests that a stiff layer (hardpan) exists below 4 m depth on SR 26C. The stiffness pro files provided means of identifying the layered systems within the sub grade or foundation as opposed to the infinitely thick homogeneous subgrades conventionally assumed in layered-theory analysis. The dif ferences between the two are demonstrated in Section 7.5. 7.3 Correlation Between Ep and gc The dilatometer modulus, Eq, obtained from the DMT was developed by Marchetti using the theory of elasticity. It is related to Young's mod ulus of elasticity, E, and Poisson's ratio, u, as follows: En = Eqn. 7. 1 [1 2) Thus, with a reasonable estimate of u one can determine the in situ elastic modulus E. However, Jamiolkowski et al. (50) have reported Cone Tip Resistance, q (MPa) Dilatometer Modulus, E0 (MPa) V 0 20 40 60 0 20 40 60 80 100 Figure 7.3 Variation of qc and Eq with Depth on SR 26A 100 Cone Tip Resistance, q c (MPa) Dilatometer Modulus, ED (MPa) 0 20 40 60 0 20 40 60 80 Figure 7.4 Variation of qc and Eg with Depth on SR 26C Cone Tip Resistance, qc (MPa) Dilatometer Modulus, ED (MPa) 0 20 40 60 0 20 40 60 80 100 ro cn Figure 7.5 Variation of qc and Eq with Depth on US 301 Cone Tip Resistance, q c (MPa) Dilatometer Modulus, ED (MPa) Figure 7.6 Variation of qc and ED with Depth on US 441 Cone Tip Resistance, q (MPa) Dilatometer Modulus, ED(MPa) po KO Figure 7.7 Variation of qc and Eg with Depth on SR 12 298 results from calibration chamber tests in which Eg was found to be equi valent to the secant modulus at 25 percent stress level (E'25) for normally consolidated cohesionless soils. Similar correlations between E'25 and qc suggest that the ratio of E'25 to qc varies from 2 to 10 or more depending on the stress history, relative density and mineralgica! composition of the soils (50). This suggests that Eg and qc are related which is generally verified by comparing the trends illustrated in Figures 7.3 to 7.7. Regression analysis of Eg and qc values were performed for each test pavement site. The results of these analyses are given in Table 7.1. Note that the analysis utilized average values of Eg and qc from each test site. Regression equations for the three SR 26 sites and SR 15C were almost identical although their R2 values varied from 0.75 to 0.97. The other test sites had higher constants with the exception of SR 15B in which the lowest slope--2.519--was obtained. Table 7.1 Relationship Between Eg and qc for Selected Test Sections in Florida Test Road County Number of Observations R2 Regression Equation SR 26A Gilchrist 24 0.850 = 3.199 c SR 26B Gilchrist 26 0.860 ed = 3.201 qc SR 26C Gilchrist 21 0.969 ed = 3.384 qc US 301 Alachua 31 0.878 eD = 5.351 qc US 441 Columbia 26 0.881 Ed = 4.188 % SR 12 Gadsden 28 0.915 ed = 4.191 qc SR 15B Martin 21 0.900 ed = 2.519 qc SR 15C Martin 22 0.752 ed = 3.300 qc SR 715 Palm Beach 25 0.850 eD = 5.330 qc 299 Figure 7.8 illustrates the plot of Eg against qc for most of the test sites. The scatter of the data may be attributed to spatial soil variability within and between test sites. Also, the variability in the relationship between Eg and qc could be affected by soil type, moisture content, and stress history. Regression analysis of the combined data resulted in the following equation: Eqn. 7.2 Eg = 3.46 qc (R2 = 0.830, N = 224) Due to the possible effect of soil type on the Eg-qc correlations, further regression analyses were performed to establish separate rela tionships for sandy and for clayey soils. The regression equations are: For sandy soils: Eg = 3.423 qc Eqn. 7.3 (R2 = 0.852, N =154) For clayey soils: Eg = 4.141 qc Eqn. 7.4 (R2 0.637, N = 70) DILATOMETER MODULUS, E ^ 100 60 40 20 0 0 10 20 30 40 CONE TIP RESISTANCE, qc, (MPa) ** i A0 A * O O X SR26A SR26B SR26C US 301 US 441 SR 12 SR15B I CO o o Figure 7.8 Correlation of ED with qc 301 The regression equation for sandy soils is almost identical to Equation 7.2 which included all the test data. The correlation for the clayey soils is poor. This poor correlation tends to agree with obser vations of Jamiolkowski et al. (50) that qc cannot be correlated to any drained soil modulus for cohesive deposits. The combined test data was also separated into above and below water table categories for the purpose of assessing whether or not the saturation state of the soils affected the Eg-qc correlations. The regression equation for above water table conditions, Ed = 3.64 qc Eqn. 7.5 (R2 = 0.926, N = 102) is similar to Equation 7.3 for sandy soils. The equation obtained for soils below water table, Ed = 3.946 qc Eqn. 7.6 (R2 = 0.778, N = 122) is almost the same as Equation 7.4 for cohesive soils. It is evident that the correlations were affected by the development of excess pore water pressures in the clayey soils during penetration. An attempt was made to measure pore water pressures using the piezocone. This was unsuccessful due to the clogging of the porous stone by fine sand particles. 302 Even though these correlations are probably site specific, the ratio of Eg to qc obtained in this investigation were within the range of values reported in the literature. However, since the CPT and DMT were performed side by side, these correlations are unique and represent improvements over other correlations which are based on comparison be tween field measured qc and laboratory determined deformation moduli. It also tends to support the argument by many engineers that the cone resistance, which is primarily an indicator of bearing capacity, can be related to soil deformation moduli. 7.4 Evaluation of Resilient Moduli for Pavement Layers 7.4.1 General One of the main objectives of this study was to assess the feasibi lity of determining the modulus of pavement layers and underlying sub grade soils using in situ penetration tests. However, Section 7.3 indicated that the parameters from the penetration tests, especially the dilatometer modulus (Eg), are related to the secant modulus at 25 per cent stress levels (E'2S) The modulus obtained from NOT generally represents the initial tangent modulus of the resultant stress-strain relationship. Because NDT and wheel loadings are generally applied in short duration of time periods, lower strain levels are obtained. Therefore, the use of in situ penetration tests' modulus values in multilayer elastic analysis would be very conservative, and overpredict pavement response. Because qc and Eg relate directly to the in situ deformation char acteristics of the soils, it was decided to correlate these parameters to the NDT tuned layer moduli. The tuned layer moduli have been 303 referred to as resilient moduli since the load-deformation character istics of flexible pavements are resilient (see Section 6.5.1). Also, because different moduli values were obtained from the Dynaflect and FWD tests, it was decided to correlate layer moduli predictions with the in situ penetration tests for both NDT devices. The correlations between pavement layer moduli and qc and Eq are presented in Section 7.4.2 and 7.4.3, respectively. The average qc and Eq values for each layer was correlated to the respective NDT tuned moduli. The first layer was excluded, since the resilient characteris tics of asphalt concrete materials are both temperature and rate of loading dependent. The effective pavement thickness (EPT) was defined to be 1 m from the pavement surface. Materials below this were assumed to have no effect on traffic-associated pavement performance. This was then used to determine the thickness of the effective subgrade layer which was therefore the difference between 1 m and the overlying pavement thick ness. This assumption is consistent with the conventional design practice in which subgrade samples immediately below the subbase layer are tested for modulus values. Also, other workers have selected similar depths for use with their penetration tests. For example, Kleyn et al. (58) considered the depth of 0.8 m for the use of the dynamic cone penetrometer in road pavements. Briaud and Shields (15) conducted their pavement pressuremeter tests to a depth of 1.8 m in airport pavements. Even though EPT could vary with pavement types and stiffness characteristics of the pavement a value of 1 m was used in this analysis. The possible effects of this and the general problem of characterizing the subgrade layer are discussed in Section 7.5. 304 7.4.2 Correlation of Resilient Moduli with Cone Resistance The average qc values determined from each layer were compared to the respective NDT tuned layer moduli. The results of these comparisons are illustrated in Tables 7.2, 7.3, and 7.4, for the base course, sub base, and subgrade layers, respectively. The ratios of tuned moduli to cone resistance presented in Tables 7.2 to 7.4 indicate that variability increases from E2 through Eg to E^. However, significantly high ratios were obtained for the base course and subbase layers for some of the pavements. For example, the SR 12 pavement had a ratio of 61.29 using the Dynaflect tuned E2 (Table 7.2). The corresponding FWD E2 to qc ratio, 15.83, does not differ much from the others in the FWD column. Also, the plate loading test results gave an E2 value of 43,000 psi (see Table 6.17) as compared to the NDT tuned values of 120,000 and 31,000 psi, respectively, with the Dynaflect and FWD deflection responses. Thus, the FWD prediction of the base course modulus on SR 12 test section may be more realistic than that of the Dynaflect. Pavement sections and layers having extremely high or low ratios were excluded in subsequent analysis of the data. Regression analyses were performed between resilient (or tuned NDT) moduli and cone resistance. The results are summarized in Table 7.5. The results suggest that the correlations are good for the base and subbase layers but poor for the subgrade. Also, the results for the combined data are similar to those for the base and subbase layers as compared to the subgrade layer. The poor correlation in the subgrade could be due to the natural variability in the subgrade soils compared to the essentially homogeneous base and subbase materials. The tech nique of determining the subgrade layer might have also affected the 305 Table 7.2 Correlation of NDT Tuned Base Course Modulus (E2) to Cone Resistance Test Road Mile Post Number Average qc (psi) Tuned E2 (psi) e2/9 c Dynaflect FWD Dynaflect FWD SR 26A 11.912 6525 105000 75000 16.09 11.49 SR 26B 11.205 6380 90000 90000 14.11 14.11 SR 26C 10.168 5075 55000 45000 10.84 8.87 SR 26C 10.166 5075 55000 55000 10.84 10.84 SR 24 11.112 8338 105000 55000 12.59 6.60 US 301 21.580 8048 120000 45000 14.91 5.59 US 441 1.236 7250 85000 55000 11.72 7.59 I-10A 14.062 7685 95000 90000 12.36 11.71 SR 15B 4.811 6815 120000 52800 17.61 7.75 SR 15A 6.549 * 120000 95000 SR 15A 6.546 * 85000 45000 SR 715 4.722 * 75000 45000 SR 715 4.720 * 65000 65000 SR 12 1.485 1958 120000 31000 61.29 15.83 SR 15C 0.055 3625 105000 35000 28.97 9.66 SR 15C 0.065 5510 105000 50000 19.06 9.07 * Test not performed 306 Table 7.3 Correlation of NDT Tuned Subbase Modulus (E3) to Cone Resistance Test Road Mile Post Number Average qc (psi) Tuned Eg (psi) E, Dynaflect FWD Dynaflect FWD SR 26A 11.912 4532 70000 45000 15.45 9.93 SR 26B 11.205 4118 60000 45000 14.57 10.93 SR 26C 10.168 4350 35000 27500 8.05 6.32 SR 26C 10.166 4350 35000 22000 8.05 5.06 SR 24 11.112 6344 75000 40000 11.82 6.31 US 301 21.580 3154 75000 35000 23.78 11.10 US 441 1.236 4350 60000 35000 13.79 8.05 I-10A 14.062 5655 89400 80000 15.81 14.15 SR 15B 4.811 6090 75000 50000 12.32 8.21 SR 15A 6.549 * 40000 39500 SR 15A 6.546 * 65000 35000 SR 715 4.722 3843 50000 25000 13.01 10.28 SR 715 4.720 3843 45000 26000 11.71 6.77 SR 12 1.485 3915 75000 20000 19.16 5.11 SR 15C 0.055 2175 75000 12000 34.48 5.52 SR 15C 0.065 2175 75000 44000 34.48 20.23 Test not performed 307 Table 7.4 Correlation of NDT Tuned Subgrade Modulus (E4) to Cone Resistance Test Road Mile Post Number Average qc (psi) Tuned E, 4 (psi) Dynaflect FWD Dynaflect FWD SR 26A 11.912 2900 14600 18700 5.03 6.45 SR 26B 11.205 2610 7900 11000 3.03 4.21 SR 26C 10.168 2175 28500 25500 13.10 11.72 SR 26C 10.166 2175 28500 20000 13.10 9.20 SR 24 11.112 4712 38600 38600 8.20 8.20 US 301 21.580 1740 38600 25000 22.18 14.37 US 441 1.236 3190 27500 20000 8.62 6.27 I-10A 14.062 5293 105000 130,000 19.84 24.56 SR 15B 4.811 3625 8100 10200 2.23 2.81 SR 15A 6.549 * 4800 7500 SR 15A 6.546 * 5000 7000 SR 715 4.722 1015 6000 11000 5.91 10.84 SR 715 4.720 1015 5500 10500 5.42 10.34 SR 12 1.485 2175 26500 18500 12.18 8.51 SR 15C 0.055 2175 5500 9800 2.53 4.51 SR 15C 0.065 2175 5500 10000 2.53 4.60 * Average qc within the depth of the difference of 1 m (EPT) and the overlying pavement ** Test not performed 308 Table 7.5 Relationship Between Resilient Modulus, and Cone Resistance, qc Dynaflect Moduli FWD Moduli Layer Regression* Equation N R2 Regression* Equation N R2 Base E2 = 13.992 qc i0(a) 0.971 E2 = 9.073 qc 12 0.921 Subbase E3 = 12.987 qc 11(b) 0.954 E3 = 7.467 qc 12(c) 0.942 Subgrade E, = 6.699 qc 12(d) 0.770 E^ = 6.853 qc 13(e) 0.856 ALL Er = 12.881 qc 33 0.931 E^ = 8.356 qc 37 0.910 * Some of the test pavements were deleted in the regression analysis. Pavements deleted are: (a) SR 12 and SR 15C M.P. 0.055 (b) US 301 and SR 15C M.P. 0.055 and 0.065 (c) SR 15C M.P. 0.065 (d) US 301 and I-10A (e) I-10A correlation since a composite (average) subgrade modulus from the NOT was used in the analysis. 7.4.3 Correlation of Resilient Moduli with Dilatometer Modulus Similar comparisons with the dilatometer modulus, Eq, for the sub base and subgrade layers were made. These are presented in Tables 7.6 and 7.7, respectively. The ratios of tuned moduli to Eq for the subbase vary more than that of the subgrade. Also the ratios obtained for the subgrade are close to unity, especially for the pavement sections with weak subgrade layers. This suggests that the dilatometer modulus may be directly related to the in situ elastic (resilient) modulus of soft subgrade soils. 309 Table 7.6 Correlation Dilatometer of NOT Tuned Modulus Subbase Modulus to Test Mile Post Average Eq Tuned E3 (psi) E 3/ed Road Number (psi) Dynaflect FWD Dynaflect FWD SR 26A 11.912 9860 70000 45000 7.10 4.56 SR 26B 11.205 11455 60000 45000 5.24 3.93 SR 26C 10.168 13340 35000 27500 2.62 2.06 SR 26C 10.166 13340 35000 22000 2.62 1.65 SR 24 11.112 * 75000 40000 US 301 21.580 8700 75000 35000 8.62 4.02 US 441 1.236 12615 60000 35000 4.76 2.77 I-10A 14.062 89400 80000 SR 15B 4.811 14065 75000 50000 5.33 3.55 SR 15A 6.549 12470 40000 39500 3.21 3.17 SR 15A 6.546 12470 65000 35000 5.21 2.81 SR 715 4.722 15718 50000 25000 3.18 1.59 SR 715 4.720 15718 45000 26000 2.86 1.65 SR 12 1.485 11673 75000 20000 6.43 1.71 SR 15C 0.055 3335 75000 12000 22.49 3.60 SR 15C 0.065 3335 75000 44000 22.49 13.19 * Test not performed 310 Table 7.7 Correlation Dilatometer of NDT Tuned Subgrade Modulus Modulus to Test Mile Post Average Eq* Tuned E, r 4 (psi) E4 ./Ed Road Number (psi) Dynaflect FWD Dynaflect FWD SR 26A 11.912 8990 14600 18700 1.62 2.08 SR 26B 11.205 11528 7900 11000 0.69 0.95 SR 26C 10.168 9933 28500 25500 2.87 2.57 SR 26C 10.166 9933 28500 20000 2.87 2.01 SR 24 11.112 ** 38600 38600 US 301 21.580 9752 38600 25000 3.96 2.56 US 441 1.236 7975 27500 20000 3.45 2.51 I-10A 14.062 105000 130000 SR 15B 4.811 11165 8100 10200 0.73 0.91 SR 15A 6.549 5365 4800 7500 0.89 1.40 SR 15A 6.546 5365 5000 7000 0.93 1.30 SR 715 4.722 7250 6000 11000 0.83 1.52 SR 715 4.720 7250 5500 10500 0.76 1.45 SR 12 1.485 7323 26500 18500 3.62 2.53 SR 15C 0.055 7250 5500 9800 0.76 1.35 SR 15C 0.065 7250 5500 10000 0.76 1.38 * Average Eq within the depth of the difference of 1 m (EPT) and the overlying pavement. ** Test not performed 311 Regression analyses were also performed between the resilient (NDT tuned) and dilatometer moduli. Table 7.8 lists results of the analysis for the subbase and subgrade layers. The correlation coefficients are lower than those obtained for the cone resistance in Table 7.5. Thus, the CPT may be more reliable than the DMT in predicting the modulus of layered pavement systems and subgrade soils. The ability of the CPT to test stiffer soils such as base course materials make it more attractive than the DMT. However, for weak subgrade soils the DMT may yield reasonable modulus predictions. Further work on the interpretation of both CPT and DMT results may be worth pursuing. Table 7.8 Relationship Between Resilient Modulus, ER and Dilatometer Modulus, ed Dynaflect Moduli FWD Moduli Layer Regression Equation N R2 Regression Equation N R2 Base * * Subbase E3 = 4.317 eD 12(a) 0.874 E3 = 2.576 Ed 13(b) 0.879 Subgrade E, = 1.855 eD 14 0.697 Eii = 1-749 Ed 14 0.882 ALL E, = 3.476 4 ed 26 0.767 e4 = 2.294 Ed 27 0.854 * Dilatometer test not conducted in base course layer NOTE: Some pavements were deleted in the regression analysis. Those pavements are: (a) SR 15C M.P. 0.055 and 0.065 (b) SR 15C M.P. 0.065 312 7.5 Variation of Subgrade Stiffness with Depth The analysis presented in Section 7.4 indicated the potential for CPT prediction of the modulus of layered pavement systems as compared to the DMT. However, the correlation of NDT tuned moduli to CPT qc values were generally better for the base and subbase layers than the subgrade layer (see Table 7.5). The poor correlation for the subgrade was attri buted, among others, to the technique of determining the effective subgrade layer. This layer was assumed to extend from the subbase- subgrade interface to a depth of 1 m from the surface of the pavement without regard to the stratification of the underlying subsoils. It is argued that depending on the relative stiffnesses of the upper layers, the zone of influence of the dynamic loads from NDT or actual wheel loadings could exceed the EPT value of 1 m used in the analysis. For a pavement section with very weak subsoil conditions, the effective subgrade layer used in the analysis is in reality an embank ment which was placed on the natural subgrade to facilitate construction of the pavement. Therefore, this layer would not be a true represen tation of the subsoil conditions on the site. However, the subgrade modulus determined from the NDT deflections and used in the correlation represents a homogeneous and isotropic semi-infinite layer, as pre viously explained. In reality, infinitely thick subgrades and homo geneous subgrades with a well-defined depth seldom exist in the field. This is substantiated by the stiffness profiles presented in Figures 7.1 to 7.7 in which there was a general tendency for the stiffness to decrease significantly to a depth of 2 m. This would mean that in principle the subgrade must be considered as two or more sublayers depending on the stratigraphy, and consequently, increasing the total 313 number of layers in the pavement structure. The possible effects of subgrade stratification on NDT deflections and pavement response are briefly discussed below. The CPT log for SR 26A, as shown in Figure 7.3, was used to assess the variability of the subgrade layer. This test section had a clay layer (approximately 0.6 m thick) at a depth of about 2 m. The water table was at a depth of 1.58 m. The CPT log was used to divide the sub- grade layer into 4 sublayers and an average qc value was assigned to each layer. The Dynaflect modulus-qc equation for the combined data in Table 7.5 was used to predict the respective layer modulus. The number of pavement layers was assumed to vary from 4 to 7, depending on the number of layers in the subgrade. BISAR was then used to predict Dyna flect deflections for the various layers. In all cases, the moduli values for the AC, base and subbase layers were kept constant. Table 7.9 shows the results of Dynaflect deflections predicted by BISAR for the various numbers of layers. The actual field measured deflections are also listed in Table 7.9. It is seen from the table that significantly different deflections were predicted by BISAR depending on the number of layers and the modulus value of the semi- infinite subgrade layer. For example, when the weak clay layer was considered as the semi-infinite layer in a 6-layer system, the predicted deflections were more than twice the measured values. However, when this weak clay layer was underlain by a relatively stiff subgrade in the 7-layer system, predicted and measured deflections were comparable. The above illustration tends to support the argument that founda tion layers with highly variable moduli significantly influence the response characteristics of nondestructive tests. The presence of a Table 7.9 Effect of Varying Subgrade Stiffness on Dynaflect Deflections on SR 26A Number of Layers Subgrade Modulus* (ksi) Dynaflect Deflections (mils) D l D 2 D 3 D 4 D 5 D 6 D 7 D 8 D 9 D 10 ** 0.87 0.81 0.77 0.68 0.61 0.53 0.45 0.39 4(a) 37.4 0.63 0.49 0.47 0.45 0.41 0.36 0.32 0.26 0.20 0.15 50>) 18.9 0.80 0.66 0.64 0.62 0.58 0.53 0.49 0.42 0.34 0.29 6(c) 2.6 1.84 1.71 1.69 1.67 1.62 1.57 1.52 1.44 1.34 1.25 7(d) 23.1 0.93 0.79 0.77 0.75 0.71 0.66 0.62 0.54 0.45 0.38 * ** (a) (b) (c) (d) Semi-infinite subgrade modulus using Dynaflect modulus qc correlation in Table 7.5 with Ex = 171.5 ksi; E2 = 105.0 ksi; E3 = 70.0 ksi; t: = 8.0 in.; t2 = 9.0 in.; t3 = 12.0 in. Field measured Dynaflect deflections 4-layer: E4 = 37.4 ksi and t4 = 5-layer: E4 = 37.4 ksi; E5 = 18.9 ksi; t4 = 10.4 in. and tg = > 6-layer: E4 = 37.4 ksi; E5 = 18.9 ksi; Eg = 2.6 ksi; t4 = 10.4 in.; tg = 19.7 in. and tg = 7-layer: E4 = 37.4 ksi; Eg = 18.9 ksi; Eg = 2.6 ksi; E? = 23.1 ksi; t4 10.4 in.; tg = 19.7 in.; t6 = 29.5 in. and t? = 00 315 clay layer at shallow depth and near the water table, as in the case of the SR 26A site, would not only contribute to a loss in foundation support, but would also channel water to the upper layers by means of capillary rise. Pore pressures could also be generated in the submerged layers which would also contribute to a reduction in foundation support. In general, a weak subgrade would result in high deflections. However, it will be shown in Chapter 8 that high deflections do not necessarily mean that the pavement is structurally deficient. Depending on the relative stiffnesses of the upper layers (AC, base and subbase), a pave ment with a weak subgrade (or high deflections) could yield moderate stresses in the various layers. But when the subbase and base course layers also become weak as a result of moisture intrusion, the entire pavement could deteriorate structurally. The variation of the subgrade stiffness with depth is also impor tant for the design of new pavements. Table 7.9 suggests that predicted deflections could differ significantly from field measured values depending on the subgrade modulus. In most design procedures, the thicknesses of the upper layers are selected based on the subgrade modulus. Therefore, if samples of the subgrade from immediately below the subbase layer are tested for modulus, use of this modulus could result in a completely wrong design. Knowledge of the stratigraphy would help to arrive at an optimum and efficient design. It is believed that the CPT has the capability of providing such important informa tion. Also, the correlations presented in Table 7.5 could be used to estimate the subgrade modulus. This could avoid the problems of deter mining subgrade modulus in the laboratory. CHAPTER 8 PAVEMENT STRESS ANALYSES 8.1 General The mechanistic approach for evaluation and design of pavement sys tems contains an important empirical component. It relies on empirical relationships between pavement response and pavement performance. In general, two relationships are used, one for predicting cracking of bound layers (e.g., asphalt concrete) and one for predicting permanent deformations (roughness or rutting) of the base course and subgrade layers. These forms of deterioration are, respectively, referred to as structural and functional by Ullidtz and Stubstad (123). The horizontal tensile stress or strain at the bottom of the asphalt concrete and the vertical strain or stress on top of the subgrade are both considered in the evaluation of flexible pavements. Essentially, these relate to the bearing capacity and riding quality, respectively, of the pavement. As suggested by Ullidtz and Stubstad (123), it would be preferable to interrelate the two relationships such that cracking is considered in the model for predicting roughness and rutting. However, this is seldom attempted in practice. Despite the empirical component, the mechanistic design process has obvious advantages over existing empirical methods which are based on the correlation between the maximum deflection under a load and pavement performance. The use of maximum deflection as an indicator of struc tural capacity may be misleading, depending upon the stiffness of the pavement layers relative to the subgrade moduli. For example, a stiff 316 317 pavement with a weak foundation layer can produce high deflections but lower load-induced stresses and strains than a so-called high quality pavement. However, the mechanistic process allows the engineer to base his decision on a rational evaluation of the mechanical properties of the materials in the existing pavement structure. The material properties, for example moduli, are then used to calculate the response parameters (stresses, strains, and displacements) under some determined loadings and environmental conditions. Pavement layer thicknesses are modified until the critical stresses or strains do not exceed permissible values. The establishment of the allowable stresses or strains is the most dif ficult part of the mechanistic approach. Therefore, empirical guide lines and relationships continue to be used. As mentioned previously, two forms of criteria are used; maximum tensile stress or strain at the bottom of AC layer, and the vertical stress or strain on top of the subgrade. These are used with empirical relationships to compute the remaining life of the pavement and overlay required to meet established criteria. The horizontal tensile stress at the bottom of the bound layer is assumed critical in evaluating the pavement's resistance to cracking. However, there are indications that the mechanisms of cracking of asphalt concrete are not fully understood and that the concepts used to analyze these cracks may not be completely val id. Existing pavement design procedures usually consider cracking of asphalt-bound layers to be caused by traffic-load-induced fatigue. Therefore, the allowable stress or strain criterion is based on the number of repetitions of vehicular loadings to reach the fatigue level. 318 However, Ruth and his co-workers (97,98) have hypothesized that cracking is a short-term phenomenon that occurs when the combined effect of tem perature and traffic loads exceed the failure limit of the asphalt concrete pavement. The research work of Roque (96) on a full-scale pavement tested at low temperatures indicated that rapid cooling pro duces sufficient temperature differential to result in thermal rippling of the pavement. Rippling of the asphalt concrete occurs when portions of the pavement lift off from the base course forming a wave-like pattern (96,97). Therefore, heavy wheel loadings applied at different temperatures can greatly influence the stress levels and cracking poten tial of asphalt concrete pavements. Also, Ullidtz and Stubstad (123) argue that field observations suggest that cracking of an asphalt layer often originates at the top of the layer and not at the bottom, as conventionally assumed. A complete review of the mechanisms of cracking is beyond the scope of the work presented herein. However, this chapter demonstrates how the moduli determined from NDT can be used to analyze the response of a pavement to load at low temperatures. Also, it is intended to show how empirical interpretation of NDT deflections can often be misleading in assessing the structural adequacy of a pavement. A rigorous analysis is not presented here. Only the short-term loading is considered, and the effect of any long-term loading (thermal stresses) are neglected. 8.2 Short-Term Load Induced Stress Analysis 8.2.1 Design Parameters The BISAR elastic layer computer program was used to calculate pavement response induced by vehicular loadings at low temperature 319 conditions. A 24-kip single axle with dual tires at 120 psi (13.0 in. between wheel centers) was used to represent truck loading conditions. Five test pavements were selected for the analysis. These are SR 26B, SR 24, US 441, SR 15C, and SR 80. Asphalt concrete moduli for the various pavement sections were computed using the rheology relationship at two low temperatures. These are 23F and 41F to represent winter conditions in northern (SR 26B, SR 24, and US 441), and southern (SR 15C and SR 80) Florida, respectively. The other pavement layer moduli were obtained from the NDT test results (Tables 6.7 and 6.10). With the exception of SR 80, the com putations were made using both Dynaflect and FWD tuned moduli for comparison purposes. For SR 80, the comparison was made for both sections, with the objective of verifying the cracking problems of Section 2. The input parameters for BISAR are listed in Tables 8.1 through 8.5 for each test site. The computer program was used to compute the critical response parameters (stresses and strains) at the bottom of the AC layer, and at the top of the base, subbase, and subgrade layers. Also computed were the maximum surface deflection under load and the percent compression of each layer. The values computed at the center of one wheel are listed in Tables 8.1 to 8.5 for each pavement site. The tabulated results generally constituted the critical responses for the various pavement systems. The interaction between pavement response and material proper ties are presented in the ensuing discussion. 8.2.2 Comparison of Pavement Response and Material Properties The results of the stress analysis for the five pavements are listed in Tables 8.1 to 8.5. The tables indicate that the responses 320 Table 8.1 Material Properties and Results of Stress Analysis for SR 26B (Gilchrist County) a) Input Parameters for BISAR Layer Description Thickness Poisson's Modulus (psi) (in.) Ratio Dynafl ect FWD 1 Asphalt Concrete 8.0 0.35 1,315,600 * 1,315,600 * 2 Limerock Base 7.5 0.35 90,000 90,000 3 Subbase 12.0 0.35 60,000 45,000 4 Subgrade semi- infinite 0.45 7,900 11,000 * Computed at 23F using rheology data (Table 5.4) b) Pavement Stress Analysis Response Parameters** Dynaflect FWD Maximum Surface Deflection (mils) 13.0 11.1 Radial stress, bottom of AC layer (psi) 89.0 90.7 Radial strain, bottom of AC layer (E-6 in./in.) 42.2 42.9 Vertical stress, top of base layer (psi) -11.1 -10.8 Radial stress, top of base layer (psi) 0.7 1.0 Vertical stress, top of subbase layer (psi) -4.3 -4.2 Radial stress, top of subbase layer (psi) 2.0 1.3 Vertical stress, top of subgrade (psi) -1.3 -1.6 Vertical strain, top of subgrade (E-6 in./in.) -166.0 -151.0 Deflection in AC layer (%) 2.3 2.7 Deflection in base layer (%) 6.3 7.2 Deflection in subbase layer (%) 8.4 9.7 Deflection in subgrade layer (%) 83.0 80.4 * Computed for single axle with dual wheels (6.0 kips/wheel) NOTE: + = tensile - = compressive 321 Table 8.2 Material Properties and Results of Stress Analysis for SR 24 (Alachua County) a) Input Parameters for BISAR Layer Description Thickness (in.) Poisson's Ratio Modulus (psi) Dynaflect FWD 1 Asphalt Concrete 2.5 0.35 1,288,100 * 1,288,100 2 Limerock Base 11.0 0.35 105,000 55,000 3 Subbase 17.0 0.35 75,000 40,000 4 Subgrade 00 0.35 38,600 38,600 * Computed at 23F using rheology data (Table 5.4) b) Pavement Stress Analysis Response Parameters** Dynaflect FWD Maximum Surface Deflection (mils) 8.1 11.7 Radial stress, bottom of AC layer (psi) 182.0 278.0 Radial strain, bottom of AC layer (E-6 in ./in.) 101.0 140.0 Vertical stress, top of base layer (psi) -58.3 -46.0 Radial stress, top of base layer (psi) -12.2 -10.5 Vertical stress, top of subbase layer (psi) -12.2 -11.8 Radial stress, top of subbase layer (psi) -0.4 -0.7 Vertical stress, top of subgrade (psi) -3.2 -3.9 Vertical strain, top of subgrade (E-6 in ./in.) -87.7 -105.0 Deflection in AC layer (X) 1.1 0.9 Deflection in base layer (X) 34.1 38.4 Deflection in subbase layer (X) 19.1 25.2 Deflection in subgrade layer (X) 44.9 35.5 * Computed for single axle with dual wheels (6.0 kips/wheel) NOTE: + = tensile - = compressive 322 Table 8.3 Material Properties and Results of Stress Analysis for US 441 (Columbia County) a) Input Parameters for BISAR Layer Description Thickness Poisson's Modulus (psi) (in.) Ratio Dynaflect FWD 1 Asphalt Concrete 3.0 0.35 1,453,200 * 1,453,200 * 2 Limerock Base 9.0 0.35 85,000 55,000 3 Subbase 12.0 0.35 60,000 35,000 4 Subgrade semi- infinite 0.40 27,500 20,000 * Computed at 23F using log = 6.4167 0.01106T for pavements at incipient failure. b) Pavement Stress Analysis Response Parameters** Dynaflect FWD Maximum Surface Deflection (mils) 10.0 12.4 Radial stress, bottom of AC layer (psi) 208.0 267.0 Radial strain, bottom of AC layer (E-6 in./in.) 93.9 115.0 Vertical stress, top of base layer (psi) -42.0 35.0 Radial stress, top of base layer (psi) -8.0 -7.1 Vertical stress, top of subbase layer (psi) -12.1 -11.4 Radial stress, top of subbase layer (psi) 0.02 -0.5 Vertical stress, top of subgrade (psi) -4.2 -4.8 Vertical strain, top of subgrade (E-6 in./in.) -155.0 -176.0 Deflection in AC layer (%) 1.0 0.8 Deflection in base layer (%) 23.8 25.8 Deflection in subbase layer (%) 17.0 21.6 Deflection in subgrade layer (%) 58.2 51.8 * Computed for single axle with dual wheels (6.0 kips/wheel) NOTE: + = tensile - = compressive 323 Table 8.4 Material Properties and Results of Stress Analysis for SR 15C (Martin County) a) Input Parameters for BISAR Layer Description Thickness Poisson s Modulus (psi) (in.) Ratio Dynaflect FWD 1 Asphalt Concrete 6.75 0.35 680,000 * 680,000 * 2 Limerock Base 12.5 0.35 105,000 50,000 3 Subbase 12.0 0.35 75,000 44,000 4 Subgrade semi- infinite 0.45 5,500 10,000 * Computed at 41F using rheology data (Table 5.4) b) Pavement Stress Analysis Response Parameters** Dynaflect FWD Maximum Surface Deflection (mils) 15.9 14.3 Radial stress, bottom of AC layer (psi) 54.4 88.5 Radial strain, bottom of AC layer (E-6 in./in.) 56.5 82.5 Vertical stress, top of base layer (psi) -23.0 -16.7 Radial stress, top of base layer (psi) -1.7 -1.6 Vertical stress, top of subbase layer (psi) -4.5 -4.8 Radial stress, top of subbase layer (psi) 2.8 1.3 Vertical stress, top of subgrade (psi) -0.95 -1.8 Vertical strain, top of subgrade (E-6 in./in.) -161.0 -173.0 Deflection in AC layer (*) 3.1 3.5 Deflection in base layer (%) 8.8 16.1 Deflection in subbase layer (%) 5.7 9.1 Deflection in subgrade layer (%) 82.4 . 71.3 * Computed for single axle with dual wheels (6.0 kips/wheel) NOTE: + = tensile - = compressive 324 Table 8.5 Material Properties and Results of Stress Analysis for SR 80 (Palm Beach County) a) Input Parameters for BISAR Layer Description Thickness (in.) Poisson's Modulus (psi) Ratio Sec. 1 Sec. 2 1 Asphalt Concrete 1.5 0.35 642,540 * 642,540 * 2 Limerock Base 10.5 0.35 45,000 26,500 3 Subbase 36.0 0.40 18,000 18,000 4 Subgrade CO 0.45 5,750 5,750 * Computed at 41F using Equation 6.3 b) Pavement Stress Analysis Response Parameters** Dynaflect FWD Maximum Surface Deflection (mils) 32.0 38.5 Radial stress, bottom of AC layer (psi) 207.0 344.0 Radial strain, bottom of AC layer (E-6 in./in.) 251.0 374.0 Vertical stress, top of base layer (psi) -87.4 -76.4 Radial stress, top of base layer (psi) -25.0 -21.8 Vertical stress, top of subbase layer (psi) -12.6 -14.7 Radial stress, top of subbase layer (psi) -1.0 -1.6 Vertical stress, top of subgrade (psi) -1.11 -1.12 Vertical strain, top of subgrade (E-6 in./in.) -191.0 -206.0 Deflection in AC layer (X) 0 0.3 Deflection in base layer (%) 27.2 41.6 Deflection in subbase layer (X) 29.4 33.4 Deflection in subgrade layer (X) 43.4 24.7 * Computed for single axle with dual wheels (6.0 kips/wheel) NOTE: + = tensile - = compressive 325 predicted using Dynaflect and FWD tuned moduli are comparable for SR 26B, US 441, and SR 15C test sites. The similarity in response predic tions for the two NDT devices may be attributed to the high stiffness of layers 1, 2, and 3 relative to the underlying layer support values. However, Table 8.2 shows that significant differences between Dynaflect and FWD occurred on SR 24 because of large differences in base course and subbase moduli even though the asphalt concrete and subgrade moduli were identical for both NDT devices. Tensile stresses were predicted in the base course and subbase layers of SR 26B and SR 15C. However, the magnitude of these stresses are too low (2.8 psi maximum at SR 15C) to be of concern. Also, verti cal stresses on top of the base course layer were higher for thin pave ments (SR 24, US 441, and SR 80) than pavements with thick AC layers (SR 26B and SR 15C). The vertical subgrade stresses were generally low, with a maximum value of 4.8 psi obtained for US 441. This value consti tutes 4.0 percent of the total vertical stress of 120 psi applied by each wheel. This value is less than the limiting 10 percent stress level conventionally used with the classical Boussinesq's solution (59,133). Thus, the relatively high stiffnesses of the pavement layers (i.e., the asphalt concrete, base, and subbase) result in a reduction in the stresses and strains on top of the subgrade. Table 8.6 lists a summary of the stress analyses for each pavement. The maximum surface deflection ranges from 8.1 to 38.5 mils. The major ity of these maximum deflections occurred in the subgrade layer, as indicated by the corresponding percent compression values. In general, high deflections were associated with pavements with low subgrade moduli. However, the high deflections obtained in most of these Table 8.6 Summary of Pavement Stress Analysis at Low Temperatures Test Road Temp. (F) NDT Device Maximum Deflection (mils) Subgrade Compression (%) Subgrade Strain* (0.0001 in./in.) AC Stress** (psi) Percent of AC Failure Stress++ QD 9£R O9 Dynaflect 13.0 83.0 1.66 89.0 22.3 OK OD Co FWD 11.1 80.4 1.51 90.7 22.7 SR 24 Dynaflect 8.1 44.9 0.88 182.0 45.5 FWD 11.7 35.5 1.05 278.0 69.5 IIS 441 Dynaflect 10.0 58.2 1.55 208.0 52.0 O FWD 12.4 51.8 1.76 267.0 66.8 SR 15C 41 Dynaflect 15.9 82.4 1.61 54.4 13.6 FWD 14.3 71.3 1.73 88.5 22.1 SR-80-1 41 Dynaflect 32.0 43.4 1.91 207.0 51.8 SR-80-2 41 Dynaflect 38.5 24.7 2.06 344.0 86.0 SR 80+ 41 Dynaflect+ 26.3 50.6 1.75 74.4 18.6 * Vertical compressive strain on top of subgrade layer ** Tensile stress at bottom of AC layer + Base course modulus increased to 85.0 ksi ++ Failure tensile stress of 400 psi 327 pavements did not necessarily mean that the pavements were structurally deficient. A maximum failure tensile stress of 400 psi can be considered a typical value for fracture of dense graded asphalt concrete mixtures when subjected to a short-term loading at low temperatures (98). Using the tensile stress at the bottom of the AC layer, the percent failure stress for each pavement was computed. This is summarized in Table 8.6 for both NOT devices. Prior investigations (98) indicate that pavements can crack when stress levels are in the range of 64 percent to 70 per cent of the failure stress. Thus, when the combined effect of load and thermal-induced stresses are considered, three out of the five pave ments, if not already cracked, would be susceptible to cracking. These are SR 24, US 441, and SR 80 test pavement sections. Field observations (Section 5.2) indicated that US 441 and Section 2 of SR 80 test pavements exhibited considerable longitudinal, trans verse, and block forms of cracking. However, the SR 24 pavement had limited or hairline forms of cracking. At the time of testing, Section 1 of SR 80 was uncracked. However, it was confirmed by Mr. W. G. Miley of the FD0T that cracks had subsequently appeared on Section 1 of SR 80 (personal communication, 1987). Table 8.3 indicates that the US 441 test pavement had relatively stiff layers and a low vertical stress (4.8 psi) on top of the subgrade. This pavement probably cracked because the viscosity of the age-hardened asphalt binder was high and the fracture strain was very low at the lower in situ temperatures. Therefore, in those environmental situa tions where rates of cooling and thermal stresses are very high, it is 328 essential that reduced stiffness be obtained by using softer and less temperature-susceptible asphalts in the asphalt paving mixture. The limerock base course moduli for the two SR 80 test sections were considerably lower than the other pavements. Based on the results of this investigation, a modulus value of 85,000 psi is considered typical of well-placed limerock materials in the state of Florida. Because the moduli of the extremely thick subbase (36 in.) and the subgrade for SR 80 were relatively low, this pavement probably cracked due to the lack of support from the upper pavement layers, primarily the base course and the thin (1.5-in. thick) asphalt concrete layers. Field observations indicated that either poor drainage conditions increased the moisture content of the base course or the as-compacted quality of the base material was poor and resulted in a substandard modulus for E2. The base course modulus for SR 80 was increased to 85,000 psi (standard base) for a stress analysis comparison to illustrate the effect of an improved base course on pavement response and stresses. The other layer moduli were kept constant and BISAR was used to compute the response of this hypothetical pavement. These results are summa rized in Table 8.7. Comparison of these results with the SR 80 test sections indicates that the percent failure stress level drops to 18.6 percent. Thus, with a proper base course modulus, this pavement could have yielded moderate stresses and good performance. Table 8.6 shows that the vertical compressive strain on top of the subgrade layer was of the order of 2.0 x 104 in./in. An axial compres sive subgrade strain of 2.6 x 10"4 in./in. corresponds to a 108 repeti tions of vehicular loading on flexible pavements (133). This limiting 329 Table 8.7 Effect of Increased Base Course Modulus on Pavement Response on SR 80 a) Input Parameters for BISAR Layer Description Thickness Poisson's Modulus (psi) (in.) Ratio Dynaflect 1 Asphalt Concrete 1.5 0.35 642,540 * 2 Limerock Base 10.5 0.35 85,000 ** 3 Subbase 36.0 0.40 18,000 4 Subgrade semi- infinite 0.45 5,750 * Computed at 23F using Equation ,6.3 ** E2 value increased for illustration purposes b) Pavement Stress Analysis Response Parameters** Dynaflect Maximum Surface Deflection (mils) 26.3 Radial stress, bottom of AC layer Radial strain, bottom of AC layer (E-6 (psi) in./in.) 74.4 129.0 Vertical stress, top of base layer Radial stress, top of base layer (psi) (psi) -98.4 -31.1 Vertical stress, top of subbase layer Radial stress, top of subbase layer (psi) (psi) -10.0 -0.7 Vertical stress, top of subgrade Vertical strain, top of subgrade (E-6 (psi) in./in.) -1.0 -175.0 Deflection in AC layer Deflection in base layer Deflection in subbase layer Deflection in subgrade layer (X) (X) (X) (X) 0 19.0 30.4 50.6 * Computed for single axle with dual wheels (6.0 kips/wheel) NOTE: + = tensile - = compressive 330 strain criteria, established by the Shell Oil Company, ensures that per manent deformation in the subgrade will not lead to excessive rutting at the pavement surface (133). The results summarized in Table 8.6 suggest that these pavements are not susceptible to functional deterioration, provided the desirable levels of moisture and loading conditions are maintained. 8.2.3 Summary The previous discussion has demonstrated that layer moduli from NOT tests can be valuable in predicting the response of a pavement to the combined effects of load and environment. Also, the use of the maximum deflections from NDT equipment as an indicator of structural adequacy may lead to erroneous interpretation. High deflections do not necessar ily mean high stresses or a structurally deficient pavement. The computations for US 441 and SR 80 suggest that the performance and response characteristics of pavement materials are highly dependent upon the effects of moisture, temperature, and the properties of the asphalt binder. A pavement's resistance to load-induced cracking can be improved by either increasing the stiffness of support layers or using a lower viscosity asphalt to eliminate excessively high asphalt concrete moduli at the minimum pavement temperatures. In those environmental situations where rates of cooling and thermal stresses are very high, it is important that both factors, improved stiffness of underlying support layers, and softer asphalts, be incorporated in the pavement's struc ture. Provision of proper drainageadequate camber, side drains, free- draining materials, etc.--would help to ensure that the in-place materials would maintain desirable levels of strength. CHAPTER 9 CONCLUSIONS AND RECOMMENDATIONS 9.1 Conclusions A research study was conducted to evaluate NDT deflection response of flexible pavements and to develop procedures for the prediction of layer moduli. The investigation included analyses of both computer- simulated and field-measured NDT data on fifteen flexible pavement sections in the state of Florida. In situ cone penetration, Marchetti dilatometer and plate bearing tests were performed on most of these pavement sections. The following conclusions were derived from the results obtained in this investigation: 1. A simplified approach which allows a layer-by-layer analysis of the Dynaflect deflection basin has been developed. This technique, which utilizes a modified Dynaflect geophone configuration (Figure F.l), provides the capability to separate the deflection response contributed by the subgrade, stabilized subgrade, and the combina tion of base and asphalt concrete layers for typical Florida flexi ble pavement systems. 2. Analyses of Dynaflect data from the fifteen in-service flexible pavements using the BISAR elastic layer computer program resulted in the development of simple power law regression equations to predict layer moduli from modified sensor deflections. A recommended test ing and analysis procedures using the modified Dynaflect testing system has been presented in Appendix F. The computational 331 332 algorithms of the recommended procedure were incorporated into the BISAR computer program to perform the iteration after the initial computation of the seed moduli. A partial listing of the DELMAPS1-- Dynaflect Evaluation of Layer Moduli for Asphalt Pavement Systems Version l--computer program is also presented in Appendix G. 3. Sensitivity analyses of theoretically-derived FWD data indicated that minor changes in Ej, E2, and E3 would not have a significant effect on the FWD deflections. Multiple linear regression analysis was utilized to develop layer moduli prediction equations from FWD deflection basins. 4. Analyses of load-deflection response from FWD tests conducted on the test pavements suggested that most of the pavement sections behave linearly. Only three pavement sections (SR 26B, SR 15A, and SR 15B) exhibited nonlinear response from the load-deflection diagrams. Further analyses revealed that nonlinearity only occurred at loads less than 6.0 kips. Therefore, FWD deflections should be measured at higher loads, preferably 9 kips to minimize the effects of nonlinearity. 5. Modeling of the FWD deflection basins for most of the test pavements was found to be very difficult as compared to the deflections ob tained with the Dynaflect. The difficulty in tuning the FWD deflec tions was attributed to the FWD plate and loading system being rigid rather than flexible. 6. Analyses of the tuned FWD data for the test sections did not result in any simplified relations for layer moduli predictions, with the possible exception of E^. Therefore, the current spacing of the geophones and loading configuration of the FWD testing system 333 (Figure 3.3) are probably not suitable to allow the separation of pavement layers from the interpretation of FWD deflections. 7. The use of viscosity-temperature relationship obtained from Schweyer Rheometer tests on the recovered asphalts was found to be an effec tive and reliable method for predicting the asphalt concrete modu lus, Analysis of the NDT data resulted in the development of Figure 6.64 which can be used as a simple and rapid method of esti mating E from the mean pavement temperature during routine NDT pavement evaluation studies. 8. Comparisons between Dynaflect and FWD tuned moduli for the various test sections indicated that the Dynaflect predicted higher base course and subbase (stabilized subgrade) moduli than the FWD. In the case of the subgrade, no distinct trend between the two NDT devices was found from the analyses. Therefore, the differences in layer moduli predictions were attributable to the inherent differ ences between the two NDT devices; namely, vibratory loading for the Dynaflect versus impact loading for the FWD testing system. 9. The penetration tests provided means for identifying the soils and also for assessing the variability in stratigraphy of test sites. The cone resistance, qc, correlated well with the dilatometer modu lus, Ed, especially for sandy soils and soils above the water table. The correlation for clayey soils was poor, supporting the argument that qc cannot be correlated to any drained soil modulus for cohesive deposits. 10. Pavement layer moduli determined from NDT data were regressed to qc and Eg for the various layers in the pavement. Good correlations were obtained for qc as compared to Eg. However, the dilatometer 334 modulus compared favorably with the NDT moduli of weak (soft) sub grade soils. Also, lower correlation coefficients were obtained for the subgrade layer, suggesting the variability of this layer as compared to the upper pavement layers. 11. Analysis of the in situ penetration tests indicated that these tests, especially the CPT, can be used to supplement NDT for the evaluation of pavements especially in locating zones of weakness in the pavement or underlying subgrade soils. 12. Stress analysis conducted on some of the pavements provided a means of establishing the possible causes of failure and/or surface cracking on US 441 and SR 80. The analysis suggested that the performance and response characteristics of pavement materials are highly dependent upon the effects of moisture, temperature, and the properties of the asphalt binder. High deflections do not necessar ily mean high stresses or a structurally deficient pavement. 9.2 Recommendations The ultimate goal of the techniques developed in this study is to alleviate the problems of determining realistic pavement layer moduli using current methods. The following recommendations for further study, based on the results obtained in this investigation, are suggested: 1. The simplified approach using the modified Dynaflect testing system would allow a large number of test points to be analyzed, and conse quently enhance our ability to carry out mechanistic pavement evalu ation on a routine basis. Therefore, it is recommended that the FDOT (and other agencies) modify one of their Dynaflect units to meet the system described herein. The modified and standard system 335 can be used side by side in research and routine pavement evaluation studies. This should include an on-board computer (PC) which can compute moduli for a four-layer pavement system using the regression equations presented in Appendix F. The PC should be capable of printing out deflection response and layer moduli profiles which could be superimposed in graphic format for visual interpretation of lineal segments of highway pavements. 2. The field tests reported herein were carried out on fifteen pavement sections at fixed levels of temperature and moisture conditions. It is recommended that additional work be conducted on other flexible pavements at various seasons of the year to establish the effects (if any) of moisture and temperature on the prediction equations. 3. The FWD layer moduli prediction equations were found to be reliable, provided the field measured deflections simulated the conditions used to develop the equations. It was suggested, among other fac tors, that the rigidity of the plate, and the load-geophone configu ration in the FWD testing system influenced field measured deflec tions. This influence makes FWD deflections deviate from those simulated from the multilayered linear elastic theory. It is there fore recommended that further study be conducted to establish proce dures to adjust field measured FWD deflections which would enhance the use of the developed layer moduli prediction equations. It is also believed that the FWD load-configuration does not provide separation of the pavement layers' response as was obtained with the Dynaflect. A modified FWD system utilizing a dual loading system appears worth pursuing in future NDT research. 336 4. Further work on the interpretation of the in situ penetration tests is required to improve the correlations obtained in this study. The use of the penetration tests to characterize the subgrade layer and the feasibility of the DMT to predict the moduli of weak subgrade soils should be investigated. 5. Additional stress analyses using load and thermal-induced stresses should be performed to establish relationships between pavement performance (stress-strain response) and material properties. 6. The algorithms obtained in this study should be used to develop a computer program for mechanistic evaluation of flexible pavements. This program should be able to predict the remaining life and/or overlay thickness of a pavement subjected to the combined effects of load and thermal-induced stresses. APPENDIX A FIELD DYNAFLECT TEST RESULTS Table A.l Results of Dynaflect Tests on SR 26A (Gilchrist County) Temperature (F): Air = 79 Pavement Surface = 82 Mid-Pavement = 81 Site No. Mile Post No. Type of Data Measured Deflections (mils) for Sensor Positions * 1 2 3 4 5 6 7 8 9 10 1 11.927 Std 0.83 0.74 0.58 0.50 0.43 2 11.922 Std 0.80 0.70 0.50 0.41 0.34 3 11.917 Std 0.81 0.68 0.54 0.45 0.38 3 11.917 Mod 1.12 0.78 0.64 0.46 0.39 3.5 11.914 Mod 0.86 0.79 0.65 0.47 0.40 4 11.912 Std 0.81 0.68 0.53 0.45 0.39 4 11.912 Mod 0.87 0.77 0.61 0.44 0.38 4.5 11.909 Mod 0.97 0.82 0.67 0.51 0.44 5 11.906 Std 0.86 0.74 0.62 0.53 0.46 6 11.901 Std 0.98 0.86 0.70 0.61 0.54 7 11.896 Std 0.97 0.87 0.74 0.67 0.60 8 11.891 Std 0.92 0.81 0.65 0.57 0.50 * Sensor positions correspond to the modified array in Figure 4.2 Table A.2 Results of Dynaflect Tests on SR 26B (Gilchrist County) Temperature (F): Air = 45 Pavement Surface = 48 Mid-Pavement = 59 Site No. Mile Post No. Type of Data Measured Deflections (mils) for Sensor Positions * 1 2 3 4 5 6 7 8 9 10 0 11.213 Std 1.05 0.99 0.79 0.68 0.68 1 11.208 Std 1.24 1.16 0.92 0.78 0.68 1 11.208 Mod 1.31 1.30 1.06 0.79 0.69 1 11.208 Std 1.22 1.14 0.89 0.75 0.66 1 11.208 Mod 1.34 1.37 1.11 0.75 0.69 1.5 11.205 Std 1.18 1.12 0.90 0.77 0.68 1.5 11.205 . Mod 1.28 1.23 0.99 0.76 0.67 2 11.202 Std 1.06 1.04 0.85 0.74 0.66 2 11.202 Mod 1.15 1.12 0.96 0.75 0.66 2.5 11.200 Std 1.12 1.09 0.89 0.78 0.70 2.5 11.200 Mod 1.25 1.21 1.02 0.81 0.73 3 11.197 Std 1.21 1.17 0.95 0.83 0.74 3 11.197 Mod 1.33 1.25 1.04 0.83 0.75 * Sensor positions correspond to the modified array in Figure 4.2 Table A.3 Results of Dynaflect Tests on SR 26C (Gilchrist County) Temperature (F): Air = 60 Pavement Surface = 60 Mid-Pavement = 82 Site No. Mi 1 e Post No. Type of Data Measured Deflections (mils) for Sensor Positions * 1 2 3 4 5 6 7 8 9 10 1 10.183 Std 0.73 0.63 0.41 0.25 0.21 2 10.178 Std 0.72 0.62 0.41 0.29 0.20 3 10.173 Std 0.79 0.69 0.45 0.28 0.18 4 10.168 Std 0.77 0.62 0.37 0.24 0.16 4 10.168 Mod 0.89 0.77 0.53 0.24 0.16 4.5 10.166 Std 0.77 0.68 0.44 0.27 0.17 4.5 10.166 Mod 0.90 0.78 0.54 0.26 0.17 5 10.163 Std 0.74 0.66 0.41 0.25 0.16 5 10.163 Mod 0.82 0.75 0.51 0.25 0.15 5.5 10.160 Std 0.76 0.65 0.42 0.27 0.18 5.5 10.160 Mod 0.75 0.79 0.55 0.27 0.18 6 10.158 Std 0.73 0.62 0.39 0.25 0.16 6 10.158 Mod 0.70 0.76 0.53 0.25 0.16 * Sensor positions correspond to the modified array in Figure 4.2 Table A.4 Results of Dynaflect Tests on SR 24 (Alachua County) Temperature (F): Air = 55 Pavement Surface = 55 Mid-Pavement = 57 Site Mile Type of Measured Deflections (mils) for Sensor Positions* No. Post No. Data 1 2 3 4 5 6 7 8 9 10 6.1 11.107 Std 0.50 0.32 0.21 0.17 0.14 6.1 11.107 Mod 0.47 0.48 0.27 0.18 0.14 6.2 11.112 Std 0.51 0.33 0.22 0.18 0.15 6.2 11.112 Mod 0.50 0.50 0.28 0.18 0.15 6.3 11.117 Std 0.51 0.33 0.21 0.18 0.14 6.3 11.117 Mod 0.44 0.51 0.28 0.17 0.14 * Sensor positions correspond to the modified array in Figure 4.2 Table A.5 Results of Dynaflect Tests on US 301 (Alachua County) Temperature (F): Air = 63 Pavement Surface = 65 Mid-Pavement = 69 Site No. Mile Post No. Type of Data Measured Deflections (mils) for Sensor Positions * 1 2 3 4 5 6 7 8 9 10 1 21.575 Std 0.42 0.32 0.22 0.16 0.13 1 21.575 Mod 0.39 0.41 0.25 0.16 0.13 2 21.580 Std 0.49 0.37 0.26 0.19 0.14 2 21.580 Mod 0.54 0.48 0.34 0.21 0.15 3 21.585 Std 0.47 0.35 0.25 0.18 0.13 3 21.585 Mod 0.62 0.46 0.30 0.23 0.14 4 21.589 Std 0.51 0.37 0.27 0.20 0.15 4 21.589 Mod 0.57 0.50 0.34 0.20 0.18 5 21.593 Std 0.43 0.33 0.24 0.18 0.15 5 21.593 Mod 0.39 0.42 0.28 0.18 0.14 * Sensor positions correspond to the modified array in Figure 4.2 Table A.6 Results of Dynaflect Tests on US 441 (Columbia County) Temperature (F): Air = 51 Pavement Surface = 56 Mid-Pavement = 79 Site No. Mile Post No. Type of Data Measured Deflections (mils) for Sensor Positions * 1 2 3 4 5 6 7 8 9 10 3 1.231 Std 0.69 0.51 0.36 0.27 0.22 3 1.231 Mod 0.64 0.62 0.44 0.27 0.22 3.5 1.236 Std 0.67 0.44 0.33 0.26 0.22 3.5 1.236 Mod 0.65 0.65 0.54 0.26 0.22 4 1.237 Std 0.68 0.52 0.34 0.26 0.22 4 1.237 Mod 0.66 0.65 0.45 0.26 0.22 5 1.241 Std 0.64 0.43 0.33 0,26 0.21 5 1.241 Mod 0.70 0.56 0.38 0.25 0.21 6 1.246 Std 0.63 0.47 0.31 0.24 0.19 6 1.246 Mod 0.71 0.59 0.41 0.23 0.19 7 1.251 Std 0.63 0.44 0.32 0.24 0.19 7 1.251 Mod 0.77 0.55 0.33 0.24 0.19 * Sensor positions correspond to the modified array in Figure 4.2 Table A.7 Results of Dynaflect Tests on I-10A (Madison County) Temperature (F): Air = 84 Pavement Surface = 106 Mid-Pavement = 104 Site No. Mi 1 e Post No. Type of Data Measured Deflections (mils) for Sensor Positions * 1 2 3 4 5 6 7 8 9 10 1 14.079 Std 0.29 0.18 0.11 0.08 0.06 1 14.079 Mod 0.31 0.27 0.14 0.08 0.05 2 14.075 Std 0.28 0.17 0.10 0.07 0.05 2 14.075 Mod 0.35 0.27 0.14 0.07 0.05 3 14.069 Std 0.28 0.19 0.11 0.08 0.06 3 14.069 Mod 0.30 0.28 0.14 0.08 0.06 4 14.065 Std 0.28 0.18 0.11 0.07 0.05 4 14.065 Mod 0.30 0.27 0.15 0.08 0.05 4.5 14.062 Std 0.29 0.18 0.10 0.07 0.05 4.5 14.062 Mod 0.30 0.28 0.16 0.07 0.05 5 14.06 Std 0.27 0.16 0.10 0.06 0.05 5 14.06 Mod 0.29 0.26 0.14 0.07 0.05 6 14.055 Std 0.27 0.17 0.10 0.06 0.05 6 14.055 Mod 0.28 0.25 0.14 0.07 0.05 * Sensor positions correspond to the modified array in Figure 4.2 Table A.8 Results of Dynaflect Tests on I-10B (Madison County) Temperature (F): Air = 80 Pavement Surface = 101 Mid-Pavement = 88 Site No. Mi 1 e Post No. Type of Measured Deflections (mils) for Sensor Positions* Data j 2 3 4 5 6 7 8 9 10 1 2.703 Std 0.46 0.29 0.17 0.12 0.09 1 2.703 Mod 0.44 0.40 0.25 0.12 0.09 1 2.703 Std 0.45 0.28 0.17 0.12 0.09 (OWP) * Sensor positions correspond to the modified array in Figure 4.2 Table A.9 Results of Oynaflect Tests on I-10C (Madison County) Temperature (F): Air = 82 Pavement Surface = 99 Mid-Pavement = 106 Site Mi 1 e Type of Measured Deflections (mils) for Sensor Positions* No. Post No. Data j 2 3 4 5 6 7 8 9 10 1 32.071 Std 0.46 0.30 0.22 0.18 0.15 1 32.071 Mod 0.70 0.43 0.29 0.18 0.15 1 32.071 Std 0.40 0.28 0.22 0.18 0.15 (OWP) * Sensor positions correspond to the modified array in Figure 4.2 Table A.10 Results of Dynaflect Tests on SR 15A (Martin County) Temperature (F): Air = 88 Pavement Surface = 110 Mid-Pavement = 120 Site No. Mile Post No. Type of Data Measured Deflections (mils) for Sensor Positions* 1 2 3 4 5 6 7 8 9 10 3 6.546 Std 1.60 1.52 1.38 1.22 1.10 3 6.546 Mod 1.54 1.53 1.40 1.13 1.03 3.5 6.549 Std 1.46 1.40 1.27 1.14 1.04 3.5 6.549 Mod 1.50 1.48 1.36 1.13 1.03 4 6.551 Std 1.48 1.44 1.29 1.14 1.03 4 6.551 Mod 1.52 1.50 1.39 1.15 1.02 5 6.556 Std 1.58 1.51 1.38 1.25 1.14 5 6.556 Mod 1.57 1.55 1.45 1.21 1.11 6 6.560 Std 1.84 1.79 1.64 1.46 1.31 6 6.560 Mod 1.80 1.84 1.70 1.40 1.26 6.5 6.563 Std 2.18 1.99 1.72 1.50 1.32 6.5 6.563 Mod 2.09 2.15 1.89 1.47 1.30 7 6.566 Std 1.83 1.74 1.53 1.36 1.22 7 6.566 Mod 1.83 1.86 1.69 1.36 1.20 * Sensor positions correspond to the modified array in Figure 4.2 Table A. 11 Results of Dynaflect Tests on SR 15B (Martin County) Temperature (F): Air = 93 Pavement Surface = 111 Mid-Pavement = 127 Site No. Mi 1 e Post No. Type of Data Measured Deflections (mils) for Sensor Positions * 1 2 3 4 5 6 7 8 9 10 1 4.803 Std 1.04 0.93 0.84 0.77 0.70 1 4.803 Mod 1.11 1.03 0.91 0.76 0.68 2 4.808 Std 1.02 0.93 0.84 0.77 0.68 2 4.808 Mod 1.09 1.01 0.92 0.76 0.67 2.5 4.811 Std 1.03 0.91 0.82 0.75 0.65 2.5 4.811 Mod 1.10 1.04 0.92 0.75 0.67 3 4.813 Std 1.01 0.90 0.80 0.73 0.65 3 4.813 Mod 1.06 1.01 0.91 0.72 0.64 4 4.818 Std 1.03 0.91 0.84 0.74 0.64 4 4.818 Mod 1.13 1.01 0.92 0.72 0.64 5 4.823 Std 1.08 0.98 0.88 0.79 0.69 5 4.823 Mod 1.09 1.06 0.95 0.76 0.67 * Sensor positions correspond to the modified array in Figure 4.2 Table A. 12 Results of Dynaflect Tests on SR 715 (Palm Beach County) Temperature (F): Air = 80 Pavement Surface = 88 Mid-Pavement = 111 Site No. Mi 1 e Post No. Type of Data Measured Deflections (mils) for Sensor Positions * 1 2 3 4 5 6 7 8 9 10 1 4.732 Std 1.17 0.96 0.86 0.75 0.71 1 4.732 Mod 1.29 1.13 0.95 0.77 0.70 2 4.727 Std 1.20 0.97 0.87 0.80 0.72 2 4.727 Mod 1.27 1.15 0.94 0.79 0.71 3 4.722 Std 1.29 1.08 0.96 0.90 0.82 3 4.722 Mod 1.37 1.23 1.02 0.88 0.80 3.5 4.720 Std 1.38 1.15 1.07 0.99 0.90 3.5 4.720 Mod 1.45 1.36 1.19 1.00 0.91 4 4.717 Std 1.31 1.15 1.06 0.98 0.90 4 4.717 Mod 1.34 1.20 1.12 0.97 0.88 5 4.712 Std 1.41 1.21 1.11 1.03 0.94 5 4.712 Mod 1.41 1.35 1.19 1.02 0.93 * Sensor positions correspond to the modified array in Figure 4.2 Table A.13 Results of Dynaflect Tests on SR 12 (Gadsden County) Temperature (F): Air = 81 Pavement Surface = 91 Mid-Pavement = 102 Site No. Mile Post No. Type of Measured Deflections (mils) for Sensor Positions* Data j** 2 3 4 5 6 1 8 9 10 1 1.472 Std 0.69 0.44 0.36 0.26 0.20 1 1.472 Mod 0.95 0.63 0.39 0.19 0.68 2 1.476 Std 0.75 0.47 0.37 0.28 0.21 2 1.476 Mod 1.20 0.70 0.47 0.21 0.78 3 1.481 Std 0.66 0.43 0.35 0.27 0.21 3 1.481 Mod 0.94 0.64 0.42 0.21 0.74 3.5 1.485 Std 0.68 0.44 0.36 0.27 0.21 3.5 1.485 Mod 1.00 0.65 0.42 0.20 0.71 . 4 1.486 Std 0.68 0.43 0.35 0.27 0.21 4 1.486 Mod 1.13 0.63 0.41 0.21 0.63 5 1.491 Std 0.67 0.43 0.35 0.26 0.20 5 1.491 Mod 1.00 0.66 0.42 0.20 0.70 , Table A.13--continued Temperature (F): Air = 81 Pavement Surface = 91 Mid-Pavement = 102 Site Mi 1 e Type of Measured Deflections (mils) for Sensor Positions* No. Post No. Data ]** 2 3 4 5 6 7 8 9 10 6 1.496 Std 0.73 0.44 0.37 0.27 0.21 6 1.496 Mod 0.78 0.64 0.44 0.22 0.78 * Sensor positions correspond to the modified array in Figure 4.2 ** Two geophones were placed near both wheels Table A. 14 Results of Dynaflect Tests on SR 15C (Martin County) Temperature (F): Air = 82 Pavement Surface = 90 Mid- Pavement = 105 Site Mile Type of Measured Deflections (mils) for Sensor Positions * No. Post No. Data 2** 2 3 4 5 6 7 8 9 10 1 0.050 Std 1.59 1.30 1.13 1.07 1.06 1 0.050 Mod 2.31 1.49 1.22 1.05 0.99 2 0.055 Std 1.53 1.33 1.15 1.03 1.00 2 0.055 Mod 2.19 1.43 1.18 0.96 1.36 3 0.060 Std 1.08 0.95 0.87 0.85 0.83 3 0.060 Mod 1.68 0.97 0.87 0.82 1.04 4 0.065 Std 1.42 1.20 1.10 1.03 1.00 4 0.065 Mod 1.79 1.26 1.13 0.96 1.04 * Sensor positions correspond to the modified array in Figure 4.2 ** Two geophones were placed near both wheels APPENDIX B FIELD FWD TEST RESULTS CO OI 45* Table B.l Results of FWD Tests on SR 26A (Gilchrist County) Temperature (F): Air = 79 Pvmt. Surf. = 82 Mid-Pvmt. = 81 Site No. Mile Post No. Measured Deflections (mils) Load (kips) D,(a) 2 3 5 6 7 o 1 1 7.87 11.8 19.7 31.5 47.2 63.0 4.48 4.4 3.8 3.2 2.5 1.7 1.2 1.0 6.928 7.3 6.3 5.3 4.2 2.9 2.0 1.6 9.096 10.2 8.8 7.6 6.0 4.3 2.9 2.4 9.104 10.2 8.8 7.6 6.0 4.3 3.0 2.4 4.656 4.6 3.8 3.2 2.4 1.6 1.2 1.0 7.152 7.9 6.5 5.6 4.3 3.1 2.1 1.8 9.096 11.0 9.0 7.7 6.0 4.3 3.0 2.5 9.136 10.9 8.9 7.7 6.0 4.4 3.1 2.5 4.536 4.3 3.5 3.0 2.2 1.6 1.2 1.0 6.912 7.2 6.1 5.2 4.1 3.0 2.1 1.8 8.968 9.8 8.2 7.1 5.6 4.1 2.8 2.4 8.936 9.7 8.1 7.0 5.5 4.0 2.9 2.4 4.512 4.5 3.7 3.0 2.2 1.5 1.1 0.9 7.008 7.7 6.3 5.3 4.0 2.8 2.0 1.6 9.080 10.5 8.6 7.3 5.6 4.0 2.7 2.2 9.128 10.6 8.7 7.4 5.6 4.0 2.7 2.2 4.536 4.0 3.3 2.9 2.1 1.6 1.1 1.0 7.056 6.8 5.8 5.0 3.9 3.0 2.1 1.8 9.048 9.3 7.7 6.8 5.4 4.0 2.8 2.3 9.072 9.1 7.7 6.7 5.3 4.0 2.8 2.3 11.922 11.917 3.5 11.914 11.912 11.909 4.5 Table B.¡--continued Temperature (F): Air = 79 Pvmt. Surf. = 82 Mid-Pvmt. = 81 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) D^a) Da 3 5 6 7 O 1 o 7.87 11.8 19.7 31.5 47.2 63.0 4.512 4.1 3.4 2.8 2.1 1.5 1.1 1.0 c 11.906 6.992 6.9 5.8 5.0 3.9 2.9 2.0 1.8 D 9.080 9.4 7.9 6.8 5.4 4.0 2.8 2.3 9.088 9.3 7.8 6.7 5.2 3.9 2.8 2.3 4.528 4.8 4.0 3.3 2.5 1.9 1.5 1.2 c 11.901 7.00 8.2 6.9 5.9 4.6 3.4 2.5 2.1 0 9.064 11.1 9.4 8.1 6.3 4.8 3.4 2.9 9.080 11.0 9.2 7.9 6.3 4.8 3.5 3.0 4.480 4.1 3.4 2.8 2.2 1.7 1.4 1.2 7 11.896 7.072 6.8 5.7 4.9 3.9 3.0 2.2 1.8 / 9.032 9.3 7.8 6.7 5.4 4.1 2.9 2.5 9.048 9.2 7.7 6.6 5.4 4.1 3.1 2.5 4.456 4.9 4.0 3.3 2.4 1.7 1.3 1.1 8 11.891 6.920 8.4 7.0 5.8 4.4 3.2 2.2 1.9 9.088 11.4 9.4 7.9 6.1 4.4 3.1 2.5 9.072 11.2 9.2 7.8 5.9 4.4 3.1 2.6 (a) Sensor No. (b) Radial Distance in inches from center of FWD load. Table B.2 Results of FWD Tests on SR 26B (Gilchrist County) Site No. 0 0.5 1 1.5 Temperature (F): Air = 45 Pvmt. Surf. = 48 Mid-Pvmt. = 59 Mile Post No. Measured Deflections (mils) Load (kips) Di(a) 2 3 D Ds D6 7 0.o(b) 7.87 11.8 19.7 31.5 47.2 63.0 4.872 5.2 4.6 4.3 3.5 2.7 2.1 1.7 7.016 8.2 7.4 6.9 5.8 4.6 3.5 2.8 9.128 11.4 10.2 9.6 8.0 6.5 4.8 3.9 9.184 11.3 10.1 9.4 7.9 6.4 4.8 3.9 4.736 5.8 5.3 5.0 4.2 3.5 2.8 1.8 7.072 9.4 8.6 8.1 7.0 5.7 4.2 3.1 9.048 12.9 11.9 11.3 9.7 7.9 5.7 4.2 9.040 12.8 11.8 11.1 9.6 7.8 5.7 4.1 4.728 6.3 5.6 5.1 4.1 3.2 2.4 2.0 6.952 10.1 9.0 8.2 6.8 5.3 4.0 3.1 9.112 14.2 12.6 11.5 9.6 7.6 5.6 4.4 9.128 14.0 12.4 11.4 9.6 7.5 5.6 4.4 4.656 4.2 3.5 3.3 2.6 1.9 1.3 0.8 6.880 7.9 7.0 6.5 5.6 4.5 3.4 2.7 9.096 10.9 9.8 9.1 7.8 6.4 4.8 3.8 9.112 10.7 9.6 8.9 7.6 6.2 4.7 3.7 4.816 4.3 3.8 3.7 3.1 2.6 2.1 1.7 7.160 6.8 6.2 5.9 5.1 4.2 3.3 2.7 9.104 9.8 8.8 8.5 7.4 6.2 4.8 3.9 9.096 9.6 8.8 8.3 7.3 6.1 4.7 3.8 11.213 11.210 11.208 11.205 11.203 GO in o 2 Table B.2--continued Temperature (F): Air = 45 Pvmt. Surf. = 48 Mid-Pvmt. = 59 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) Di(a) a D3 D, 5 6 7 o O cr 7.87 11.8 19.7 31.5 47.2 63.0 4.664 4.8 4.3 4.0 3.5 2.8 2.2 1.8 0 c 11.200 7.072 7.6 7.0 6.5 5.6 4.7 3.5 2.8 9.048 10.5 9.8 9.1 8.0 6.5 5.0 3.9 9.080 10.50 9.7 9.0 7.9 6.6 5.1 4.0 4.552 4.8 4.3 4.0 3.3 2.7 2.1 1.8 Q 11.197 6.880 7.6 6.7 6.3 5.3 4.2 3.2 2.6 0 9.104 10.6 9.5 8.8 7.5 6.1 4.6 3.7 9.128 10.5 9.4 8.8 7.5 6.1 4.7 3.8 (a) Sensor No. (b) Radial Distance in inches from center of FWD load Table B.3 Results of FWD Tests on SR 26C (Gilchrist County) Temperature (F): Air = 60 Pvmt. Surf. = 60 Mid-Pvmt. = 82 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) D2 3 \ 5 D6 07 0.0(b) 7.87 11.8 19.7 31.5 47.2 63.0 4.592 5.6 4.7 4.1 3.1 2.0 1.2 0.8 6.864 8.8 7.5 6.7 5.0 3.3 2.0 1.4 9.112 12.1 10.4 9.1 7.0 4.6 2.8 2.0 9.080 11.9 10.2 8.9 6.9 4.6 2.9 2.0 4.696 5.3 4.5 4.1 3.1 2.1 1.3 0.8 6.912 8.1 7.1 6.3 5.0 3.4 2.0 1.4 9.088 11.1 9.7 8.7 6.9 4.8 2.9 2.0 9.056 11.0 9.6 8.6 6.8 4.8 2.9 2.0 4.592 6.4 5.4 ' 4.7 3.5 2.2 1.3 0.9 6.736 9.9 8.4 7.4 5.5 3.5 2.0 1.3 9.056 13.5 11.4 10.1 7.6 4.9 2.8 1.9 9.032 13.2 11.2 9.9 7.4 4.8 2.8 1.8 4.576 6.1 5.2 4.5 3.3 2.1 1.1 0.7 6.744 9.5 8.1 7.1 5.2 3.3 1.8 1.1 9.064 13.0 11.0 9.6 7.2 4.6 2.5 1.6 9.032 12.8 10.8 9.4 7.0 4.5 2.5 1.5 4.40 6.3 5.3 4.7 3.4 2.1 1.1 0.8 6.984 10.4 8.8 7.7 5.8 3.6 2.0 1.3 9.008 13.4 11.4 9.9 7.5 4.8 2.6 1.6 9.048 13.3 11.3 9.8 7.4 4.8 2.7 1.7 10.183 10.178 10.173 3.5 10.17 10.168 CO cn 00 4 Table B.3--continiied Temperature (F): Air = 60 Pvmt. Surf. = 60 Mid-Pvmt. = 82 Mile Applied Measured Deflections (mils) j 1 vL No. Post Load 0i Table B.5--continued Temperature (F): Air = 63 Pvmt. Surf. = 65 Mid-Pvmt. = 69 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) Di(a) 2 3 d5 6 D7 -Q O O 7.87 11.8 19.7 31.5 47.2 63.0 5.008 7.5 5.4 4.1 2.6 1.3 0.7 0.8 4 21.589 8.936 15.1 11.2 9.0 5.9 3.5 2.0 1.4 8.968 14.1 10.6 8.4 5.6 3.4 2.0 1.4 4.80 7.2 4.9 3.6 2.2 1.2 0.7 0.6 5 21.593 9.12 15.9 11.4 8.8 5.6 3.0 1.7 1.3 9.104 15.6 11.3 8.7 5.6 3.2 1.8 1.1 (a) Sensor No. (b) Radial Distance in inches from center of FWD load Table B.6 Results of FWD Tests on US 441 (Columbia County) Temperature (F): Air = 51 Pvmt. Surf. = 56 Mid-Pvmt. = 79 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) Dx(a) D2 3 4 D D 5 6 7 0.0(b) 7.87 11.8 19.7 31.5 47.2 63.0 5.224 8.4 6.3 5.0 3.2 2.1 1.4 1.1 1.231 8.944 15.8 12.2 9.8 6.7 4.2 2.8 2.1 8.920 15.6 12.0 9.7 6.8 4.4 2.8 2.1 5.416 9.0 5.5 4.2 2.9 2.0 1.4 1.1 CO cr> 1.236 9.20 16.3 11.0 8.7 6.0 4.0 2.7 2.0 9.152 15.6 10.6 8.4 5.8 4.0 2.8 2.0 CO 1.236 (OWP) 5.312 9.7 6.9 5.0 3.0 1.8 1.3 1.0 8.824 16.4 12.2 9.4 6.1 3.8 2.6 1.9 8.808 16.4 12.2 9.4 6.1 3.8 2.6 1.9 5.208 8.4 6.2 4.7 2.5 2.0 1.3 1.0 1.237 8.976 16.1 12.3 9.7 5.4 3.8 2.6 1.9 8.976 15.4 11.8 9.4 5.2 3.9 2.7 2.0 5.48 7.8 5.7 4.5 3.0 2.0 1.5 1.0 1.241 9.152 13.9 10.6 8.5 5.9 3.9 2.8 1.9 9.104 13.6 10.5 8.4 5.9 4.0 2.7 1.9 5 Table B.6--continued Temperature (F): Air = 51 Pvmt. Surf. = 56 Mid-Pvmt. = 79 Site Mo. Mile Applied Measured Deflections (mils) Post No. Load (kips) Di(a) D2 3 D* 5 6 7 o o cr 7.87 11.8 19.7 31.5 47.2 63.0 5.336 7.9 6.1 4.8 2.7 1.8 1.2 1.0 6 1.246 8.936 14.6 11.5 9.3 5.7 3.5 2.2 1.5 8.928 14.1 11.1 8.9 5.6 3.4 2.3 1.6 5.448 7.8 5.9 4.5 2.8 1.8 1.3 1.0 7 1.251 8.872 13.3 10.2 8.0 5.1 3.4 2.2 1.6 8.872 13.0 10.1 7.9 5.1 3.5 2.3 1.6 (a) Sensor No. (b) Radial Distance in inches from center of FWD load Table B.7 Results of FWD Tests on I-10A (Madison County) Temperature (F): Air = 84 Pvmt. Surf. = 106 Mid-Pvmt. = 104 Site Mo. Mile Applied Measured Deflections (mils) Post M/% Load (kips) D D 1 2 3 D, 5 D6 7 llO 0.0(b) 7.87 11.8 19.7 31.5 47.2 63.0 4.672 5.4 2.3 1.6 0.8 0.5 0.2 0.3 14.079 8.960 10.0 4.5 3.2 1.8 1.0 0.6 0.4 8.984 9.3 4.4 3.1 1.8 1.0 0.5 0.4 4.784 4.9 2.3 1.6 0.9 0.4 0.2 0.2 14.075 9.04 8.9 4.4 3.2 1.8 0.9 0.5 0.3 8.952 8.7 4.3 3.2 1.8 0.9 0.4 0.3 U> 4.592 4.5 2.2 1.6 0.9 0.5 0.2 0.2 CJ1 14.069 8.992 8.4 4.2 3.2 1.8 1.0 0.4 0.3 9.000 8.2 4.2 3.2 1.8 0.9 0.4 0.3 4.736 4.8 2.3 1.7 0.9 0.4 0.2 0.2 14.065 9.120 8.7 4.5 3.3 1.9 0.9 0.4 0.3 9.056 8.5 4.4 3.2 1.9 0.8 0.4 0.3 4.664 4.5 2.2 1.6 0.9 0.4 0.2 0.1 14.062 9.128 8.2 4.4 3.4 1.9 0.8 0.4 0.3 9.104 8.0 4.4 3.4 1.9 0.9 0.5 0.4 1 A nco 4.92 3.5 2.2 1.5 0.8 0.4 0.2 0.1 14* Ub / r\i m\ 9.152 6.4 4.0 2.9 1.6 0.8 0.4 0.3 (OWP) 9.064 6.4 4.0 2.9 1.6 0.8 0.4 0.3 4.5 Table B.7--continued Temperature (F): Air = 84 Pvmt. Surf. = 106 Mid-Pvmt. = 104 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) D](a) 2 3 4 D5 6 D7 0.o(b) 7.87 11.8 19.7 31.5 47.2 63.0 4.72 4.5 2.4 1.5 0.6 0.0 0.5 0.1 5 14.06 9.136 7.8 4.5 3.2 1.7 0.8 0.4 0.3 9.136 7.7 4.5 3.2 1.8 0.7 0.4 0.4 4.824 4.2 2.0 1.4 0.2 0.0 0.8 0.5 6 14.055 8.872 7.0 4.3 3.1 1.7 0.8 0.4 0.3 8.808 7.0 4.3 3.1 1.7 0.8 0.6 0.4 (a) Sensor No. (b) Radial Distance in inches from center of FWD load Table B.8 Results of FWD Tests on I-10B (Madison County) Temperature (F): Air = 80 Pvmt. Surf. = 101 Mid-Pvmt. = 88 Site Mile Applied Measured Deflections (mils) No. Post No. Load (kips) 2 3 4 5 6 7 o.o(b) 7.87 11.8 19.7 31.5 47.2 63.0 2.703 (OWP) 4.40 6.3 3.5 2.5 1.3 0.8 0.4 0.4 1 8.928 8.968 12.0 11.5 7.3 7.1 5.3 5.2 3.2 3.0 1.7 1.7 1.1 1.1 0.9 0.9 (a) Sensor No. (b) Radial Distance in inches from center of FWD load. Table B.9 Results of FWD Tests on I-10C (Madison County) Temperature (F): Air = 82 Pvmt. Surf. = 99 Mid-Pvmt. = 106 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) D2 3 5 6 D7 o.o VO 7.008 10.04 8.11 7.60 6.97 6.06 5.08 4.21 9.057 13.15 10.59 9.92 9.06 7.80 6.42 5.31 4.656 6.38 5.43 4.92 4.21 3.43 2.76 2.28 6.551 7.008 11.89 10.35 9.41 8.11 6.65 5.24 4.37 9.026 15.51 13.50 12.24 10.47 8.50 6.57 5.28 4.608 6.93 5.35 4.88 4.13 3.50 2.91 2.36 6.556 7.023 13.23 10.55 9.65 8.39 6.97 5.83 4.72 8.994 17.44 13.98 12.80 11.02 9.13 7.36 5.98 4.513 9.92 6.85 5.94 5.12 4.29 3.54 2.91 6.560 6.912 17.56 12.83 11.30 9.88 8.15 6.69 5.35 8.962 22.83 16.89 14.96 12.95 10.55 8.50 6.69 6 Table B.10--continued Temperature (F): Air = 88 Pvmt. Surf. = 110 Mid-Pvmt. = 120 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) Di(a) 3 5 Ds 7 0.o(b) 7.87 11.8 19.7 31.5 47.2 63.0 6.5 6.563 4.576 6.912 8.851 11.30 19.45 25.24 7.68 14.06 18.46 6.57 12.40 16.42 5.63 10.63 13.94 4.53 8.62 11.10 3.66 6.89 8.58 2.91 5.39 6.65 7 6.566 4.545 6.880 8.930 8.86 15.71 20.43 6.10 11.65 15.28 5.51 10.59 13.98 4.69 9.02 11.89 3.86 7.44 9.72 3.15 6.02 7.68 2.56 4.92 6.18 (a) Sensor No. (b) Radial Distance in inches from center of FWD load Table B.ll Results of FWD Tests on SR 15B (Martin County) Temperature (F): Air = 93 Pvmt. Surf. = 111 Mid-Pvmt. = 127 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) Dl(a) 02 d3 d. DS 7 0.o(b) 7.87 11.8 19.7 31.5 47.2 63.0 4.433 8.86 5.83 4.61 3.35 2.56 2.13 1.73 4.803 6.801 14.65 10.04 8.35 6.14 4.69 3.86 3.11 8.994 19.29 13.35 11.10 8.43 6.50 5.24 4.17 4.465 6.77 4.69 3.66 2.76 2.28 1.97 1.69 4.808 6.865 12.13 8.74 7.17 5.67 4.49 3.62 2.99 9.026 15.98 11.50 9.49 7.52 6.06 4.84 4.02 4.513 8.35 5.51 4.13 3.03 2.44 2.09 1.77 4.811 6.769 14.17 10.0 7.95 6.02 4.69 3.78 3.07 8.962 18.39 13.07 10.71 8.19 6.42 5.04 4.02 4.811 (OWP) 4.354 5.94 4.61 3.98 3.31 2.80 2.44 1.97 6.928 10.87 8.58 7.56 6.34 5.08 4.09 3.27 9.026 14.49 11.38 10.12 8.54 6.89 5.43 4.37 4.481 7.68 4.88 3.90 2.95 2.52 2.01 1.77 4.813 6.817 13.27 9.17 7.56 5.92 4.69 3.74 3.11 8.946 17.32 12.17 10.20 8.07 6.42 5.12 4.13 3 Table B.ll--continued Temperature (F): Air = 93 Pvmt. Surf. = 111 Mid-Pvmt. = 127 Site Mile Applied Measured Deflections (mils) D[(a) No. Post No. Load (kips) 2 3 D4 DS 6 7 o o 1 2 7.87 11.8 19.7 31.5 47.2 63.0 4.529 10.59 6.42 4.80 3.31 2.56 2.24 1.89 4 4.818 7.214 16.81 10.98 8.70 6.42 4.84 3.78 3.19 9.057 21.34 14.33 11.65 8.66 6.50 5.08 4.17 4.560 10.75 5.98 4.65 3.31 2.44 2.17 1.85 5 4.823 6.928 17.60 10.83 8.86 6.65 5.04 3.90 3.19 8.867 22.52 14.17 12.05 9.06 6.73 5.31 4.29 (a) Sensor No. (b) Radial Distance in inches from center of FWD load Table B.12 Results of FWD Tests on SR 715 (Palm Beach County) Temperature (F): Air = 80 Pvmt. Surf. = 88 Mid-Pvmt. = 111 Site No. Mile Post No. Applied Load (kips) Measured Deflections (mils) DU) 2 D3 D, D5 D7 i ^ o ! o 1 7.87 11.8 19.7 31.5 47.2 63.0 4.703 9.13 5.08 3.43 2.32 2.05 1.85 1.69 1 4.732 7.039 14.21 8.23 5.75 4.02 3.54 3.15 2.83 9.010 18.35 10.79 7.52 5.24 4.69 4.06 3.54 4.672 10.55 5.47 3.58 2.44 2.09 1.85 1.61 2 4.727 7.103 16.14 8.62 5.91 3.98 3.46 3.07 2.76 9.042 20.47 11.18 7.68 5.24 4.49 3.94 3.46 4.56 10.59 6.10 4.09 2.60 2.28 2.01 1.85 3 4.722 7.039 16.34 9.49 6.42 4.25 3.74 3.39 3.07 9.026 20.94 12.20 8.35 5.47 4.76 4.17 3.70 4.815 8.54 5.47 3.78 2.72 2.24 2.05 1.85 3.5 4.720 7.246 12.99 8.62 6.22 4.37 3.78 3.39 2.91 8.803 16.02 10.67 7.83 5.67 4.84 4.25 3.78 4.735 8.82 5.47 3.74 2.72 2.32 2.17 1.97 4 4.717 7.135 13.27 8.43 5.94 4.37 3.82 3.50 3.11 9.026 17.17 11.02 7.99 5.91 5.16 4.57 4.09 4.783 7.76 5.31 3.90 2.87 2.48 2.24 1.97 5 4.712 7.151 12.36 8.58 6.38 4.69 4.09 3.58 3.15 8.978 16.42 11.42 8.62 6.46 5.55 4.92 4.25 (a) Sensor No. (b) Radial Distance in inches from center of FWD load. Table B.13 Results of FWD Tests on SR 12 (Gadsden County) Temperature (F): Air = 81 Pvmt. Surf. = 91 Mid-Pvmt. = 102 Site No. 1 2 3 3.5 Mile Post No. Measured Deflections (mils) Load (kips) Di(a) d2 3 5 6 7 0.o(b) 7.87 11.8 19.7 31.5 47.2 63.0 4.568 15.3 7.4 4.9 2.7 1.8 1.3 0.9 6.952 27.3 12.5 8.3 4.7 2.9 1.9 1.6 9.160 31.3 16.7 11.4 6.6 4.2 2.8 2.1 9.168 27.2 16.1 11.1 6.6 4.3 3.0 2.2 4.48 17.0 8.5 4.9 3.3 1.8 1.2 1.1 6.624 25.7 14.0 8.7 4.6 3.1 2.2 1.4 8.688 32.6 18.4 11.8 6.5 4.4 2.9 2.2 8.744 29.3 17.5 11.3 6.3 4.4 3.0 2.3 4.592 14.5 8.4 4.9 2.7 1.9 1.3 1.0 6.872 21.7 13.1 8.0 4.4 3.0 2.0 1.6 9.032 28.0 17.2 10.9 6.2 4.4 2.8 2.0 9.120 26.0 16.2 10.3 6.0 4.2 2.9 2.1 4.696 17.1 9.5 5.5 3.2 2.0 1.3 1.3 6.920 22.7 13.9 8.6 5.1 2.8 1.9 1.4 9.232 29.9 19.0 12.1 6.6 4.2 2.8 2.2 9.288 29.6 18.0 11.6 6.5 4.3 2.8 2.4 4.568 11.4 6.8 4.7 3.0 2.4 1.4 1.0 6.696 21.7 11.7 8.1 4.6 2.6 2.0 1.6 8.76 25.0 15.5 11.0 6.6 4.2 2.8 2.2 8.776 22.6 15.1 10.8 6.6 4.2 2.9 2.3 1.472 1.476 1.481 1.485 1.485 (OWP) GJ 45 3.5 Table B.13--continued Temperature (F): Air = 81 Pvmt. Surf. = 91 Mid-Pvmt. = 102 Site No. Mile Applied Measured Deflections (mils) Post No. Load (kips) D2 D3 05 D7 o.o 3 Table B.14--continued Temperature (F): Air = 82 Pvmt. Surf. = 90 Mid-Pvmt. , = 105 Site No. Mile Applied Measured Deflections (mils) Post Load D2 3 D4 5 6 7 No. IKips; o o ! o i 7.87 11.8 19.7 31.5 47.2 63.0 4.799 9.25 7.01 5.98 4.53 3.15 2.32 2.01 3 0.060 6.785 13.07 10.04 8.46 6.38 4.25 2.76 2.13 (OWP) 8.883 17.80 13.78 11.81 8.94 6.14 4.21 3.39 8.867 17.24 13.31 11.34 8.58 5.83 4.09 3.35 4.831 8.90 6.61 5.51 4.09 3.11 2.36 2.20 A n n£tr 6.737 12.32 9.25 7.83 5.71 4.17 3.03 2.60 4 U UuO 8.803 16.46 12.52 10.63 7.95 5.94 4.37 3.86 8.851 15.98 12.24 10.31 7.80 5.83 4.45 3.94 4.719 7.83 6.42 5.12 4.09 3.07 2.56 2.36 4 0.065 6.801 11.26 9.17 7.36 5.75 4.17 2.99 2.60 (OWP) 8.883 15.83 12.80 10.63 8.54 6.38 4.88 4.17 8.851 15.04 11.73 9.96 7.80 5.94 4.69 4.02 (a) Sensor No. (b) Radial Distance in inches from center of FWD load APPENDIX C COMPUTER PRINTOUT OF CPT RESULTS JOB 0 2 PATE i 10-31-85 11.00 LOCATION. SR 26 A SITE ITS FILE 0 CPT 87 LOCAL FNJCriUN FRICTION NAT1U 0 TIP RESISTANCE 50 0 500 0 (PERCENT) 8 379 380 0 TIP RESISTANCE (MN/m'2) JD0 0 3 DATE i 10-31-63 13.30 LOCATION i SR 26^- SvTC FILE # i CPT 70 LOCAL FRICTION FRICTION RATIO 50 0 (kN/m2) 500 0 (PERCENT) 8 14 381 joa § i 6 DATE i 11/4/65 ID. 45 LOCATION SR-26e SITe I-IS FILE # i CPT 83 LOCAL FRICTION FRICTION RATIO 382 JOB 5 PATE 02/15/02 23*591 LOCATION. SR-26A S\TE 3-0 FILE 0 CPT 80 LOCAL FRICTION FRICTION RATIO 383 JOB i 9 OATE 11/4/65 tZ.OO LOCATION. SR-26C ilTE 4-.2.S FILE 0 CPT 86 joq 0 i e PATE i 11/4/8S 11.40 LOCATION i SR-26C SITE S'- O FILE 0 i CPT 85 LOCAL FRICTION FRICTION RATIO 385 J08 # 1 DATE 12/03/85 09(38 LOCATION SR-2*(WALDO R0> SlTt O-S FILE # CPT 10 LOCAL FRICTION FRICTION RATIO 386 JOB 0 I PATE i 12/03/03 00 34 LOCATION SR2* (WALDO R0> &V*V£ 2 S FILE 0 CPT tZ LOCAL FRICTION FRICTION RATIO 387 JOB 0 1 DATE i 02-18-06 10*49 LOCATION. SR 301 SvTE 3 5 FILE 0 CPT 93 LOCAL FRICTION FRICTION RATIO 0 TIP RESISTANCE (MN/m"2) 50 0 (hN/m*2) SOO 0 (PERCENT) 8 388 JOB 0 t 1 DATE i 02-10-86 11.29 LOCATION SR 301 Si "HE. 3-5 FILE 0 i CPT 9S LOCAL FRICTION FRICTION RATIO 0 TIP RESISTANCE 500 0 (PERCENT) 6 392 JOB # i 1 PATE i 03/18/80 D9t 23 LOCATION 1-10* S|T£ FILE 0 CPT107 LOCAL FRICTION FRICTION RATIO 0 TIP RESISTANCE V A >V A A A AAAAAA*AAAA* 0.63 4060. n.RO 29.10 679. 2.16 73.48 0.000 2.150 0.123 57.93 A A A A A 8.71 42.1 2978.7 SILTY SAND 0.83 3403. 7.60 25.30 620. 2.58 42.64 0.000 2.000 0.162 26.77 A A A A A 5.01 42.3 2403.1 SILTY SAND 1.03 2630. 6.40 22.20 351. 2.73 28.85 0.000 2.000 0.202 16.30 80.88 3.42 41.2 1931.1 SILTY SAND 1.23 2355. 6.00 22.80 588. 3.16 22.28 0.000 2.000 0.241 12.05 50.07 2.67 40.7 1914.9 SILTY SAND 1.43 I960. '<. 10 16.50 427. 3.34 13.25 0.000 1.900 0.278 4.87 17.53 1.56 41.4 1182.2 SAND 1.63 1005. 3.10 9.00 191. 1.83 9.70 0.006 1.900 0.309 3.70 11.94 1.32 36.5 471.0 SILTY SAND 1.83 290. 0.80 1.50 1. 0.03 2.95 0.026 1.500 0.319 0.59 1.84 0.77 0.114 1.4 MUD 2.03 375. 0.60 2.30 38. 1.61 2.03 0.045 1.600 0.331 0.41 1.24 0.47 33.5 36.5 SANDY SILT 2.23 1300. 2.30 15.10 442. 7.08 5.16 0.065 1.900 0.349 1.01 2.89 0.63 40.8 850.8 SAND 2.3 1270. 2.50 18.40 555. 8.77 4.98 0.084 1.900 0.366 1.04 2.83 0.63 40.4 1051.1 SAND 2.63 1045. 1.20 13.20 413. 17.01 1.83 0.104 1.800 0.382 0.13 0.34 0.21 41.3 423.2 SAND 2.83 1100. 0.50 9.10 289. 55.57 0.38 0.124 1.700 0.396 245.6 SAND 3.43 14 50. 1 70 11.30 326. 7.56 2.8?. n. in:i I. non 0.44 0 0.32 0.73 0.30 42.0 4 55.7 RAND 3.63 1040. 3.20 9.30 198. 1.97 6.33 0.202 1.900 0.458 1.95 4.27 0.76 41.3 409.9 SILTY SAND 3.83 1780. 6.10 14.40 278. 1.41 11.90 0.222 1.950 0.476 8.35 17.53 1.58 37.1 740.7 SANDY SILT 4.03 1535. 8.50 17.00 285. 1.02 16.24 0.241 1.950 0.495 12.98 26.23 2.46 844.2 SILT 4.23 1345. 7.30 14.00 220. 0.92 13.45 0.261 1.950 0.514 10.04 19.55 2.20 610.9 SILT 4.43 1090. 7.20 12.20 158. 0.66 12.91 0.281 1.950 0.532 9.77 18.35 2.15 1.205 432.6 CLAYEY SILT 4.63 905. 5.60 11.30 183. 1.01 9.52 0.300 1.800 0.548 6.25 11.41 1.78 449.2 SILT 4.83 930. 6.60 11.80 165. 0.76 10.98 0.320 1.950 0.567 8.08 14.26 1.95 1.048 427.3 CLAYEY SILT 5.03 1070. 0.20 19.00 333. 1.12 14.65 0.340 1.950 0.585 13.08 22.34 2.32 951.9 SILT 5.23 960. 5.SO 11.90 198. 1.07 8.89 0.359 1.800 0.601 6.15 10.24 1.71 471.4 SILT 5.43 820. 6.50 11.00 140. 0.66 9.89 0.379 1.800 0.617 7.47 12.11 1.83 1.001 347.3 CLAYEY SILT 5.63 830. 5.50 9.40 118. 0.66 8.08 0.398 1.800 0.632 5.58 8.83 1.61 0.797 268.6 CLAYEY SILT END OF SCI "IDT NO 406 407 UHIV. OF FLORIDA CIVIL ERG. DEPT.- DR. B.E. RUTH TEST NO. 2 FILE NAME: PAVHENT-SUEGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED,MARCH 80) K0 IN SANDS DETERMINED USING SCHMERTMANN METHOD (1983) IHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) IHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: 2SR 26A (GILCHRIST CO.) TEST SITE #4.5 PERFORMED DATE: 10-31-85 BY: JLD/DGB/KBT CALIBRATION INFORMATION: DELTA A = 0.22 BARS DELTA B = 0.45 BARS GAGE 0 0.05 BARS GWT DEPTH- 1.57 M ROD DIA.= 4.80 CM FR.RED.DIA.= 3.70 CM ROD WT. 6.50 KG/M DELTA/FHI= 0.50 BLADE 1=13.70 M 1 BAR = 1.019 KG/CM2 1.044 TSF 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 z THRUST A B ED ID KD UO GAM4A SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 1.03 3295. 10.40 32.00 763. 2.31 49.60 0.000 2.150 0.192 48.00 ***** 5.99 39.5 3062.7 SILTY SAND 1.43 2390. 4.10 16.20 416. 3.24 13.62 0.000 1.900 0.271 4.61 16.99 1.52 42.8 1163.0 SILTY SAND 2.03 645. 0.80 5.80 158. 6.42 2.13 0.045 1.700 0.332 0.29 0.87 0.36 38.0 182.6 SAND 2.43 1920. 3.80 21.60 624. 5.94 8.33 0.084 1.900 0.364 2.55 7.01 0.98 41.6 1461.1 SAND 3.03 3890. 7.40 33.90 941. 4.42 14.62 0.143 2.000 0.420 8.41 20.03 1.66 43.1 2691.1 SAND 3.63 1595. 4.80 14.00 311. 2.06 9.13 0.202 1.900 0.476 4.98 10.47 1.23 37.7 750.6 SILTY SAND 4.03 805. 2.60 5.00 63. 0.74 4.82 0.241 1.700 0.507 2.00 3.94 1.13 0.335 110.8 CLAYEY SILT END OF SOUNDING 408 UNIV. OF FLORIDA CIVIL EDO. DEFT.- DR. B.E. RUTH TEST NO. 1 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF PIIARTIETER TEST NO. 1 US I NO DATA REDICTION rROCEDURES IN MARCIIETTI (ABCE.J GED, MARCH BO) KO IN SANDS DETERMINED USING SCIHERTT1ANN METHOD (1983) mi ANGLE CALCULATION BASED ON DURGUUOGLU AND MITCHELL (ASCE.RALEIGH CONF.JUNE 75) FHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXFRESSION (ASCE, J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED.JUNE 82) LOCATION: SR 26B (GILCHRIST CO.) TEST SITE #1.0 PERFORMED DATE: 11-05-85 BY: JLD/DGB/KBT CALIBRATION INFORMATION: DELTA A 0.2.8 BARS DELTA B 0.32 BARS GAGE 0 - 0.05 BARR GWT DEFTH-* 1.05 M Ron dta.- *.nn cm FR.RFn.nTA." 3.70 m Ron wr, 6.50 KG/M pFT.TA/nu- n.5o nr.ape T-13.70 m 1 PAR 1.01 KG/CM2 = 1.0*4 TRF - 14.51 FSI ANALYSIS USES H20 UNIT WEIGHT 1.000 T/M3 z THRUST A B ED ID KD UO GAEMA sv FC OCR KO CU FHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ****** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ****** ************ 0.59 2615. * .80 27.10 791. 5.78 34.30 0.000 2.000 0.115 10.41 90.56 3.72 45.2 2899.3 SAND 0.79 3515. 17.60 0.00 794. 1.37 ***** 0.000 2.100 0.156 ***** ***** 13.04 34.9 3769.2 SANDY SILT 0.99 3270. 5.40 26.60 751. 4.70 23.53 0.000 2.000 0.195 8.99 46.01 2.57 44.4 2484.5 SAND 1.19 1900. 5.40 17.60 423. 2.42 22.79 0.014 2.000 0.221 12.10 54.75 2.78 39.3 1386.2 SILTY SAND 1.39 760. 1.30 3.90 73. 1.50 5.95 0.033 1.700 0.235 1.01 4.32 0.78 38.6 145.6 SANDY SILT 1.59 335. 0.20 1.00 7. 0.57 1.50 0.053 1.500 0.245 0.16 0.64 0.40 0.038 6.2 MUD 1.79 260. 0.30 1.20 11. 0.71 1.74 0.073 1.500 0.254 0.20 0.80 0.47 0.047 9.3 MUD 1.99 1060. 7.10 11.80 149. 0.61 25.76 0.092 1.950 0.273 14.71 53.89 3.21 1.466 507.3 CLAYEY SILT 2.19 2155. 4.60 18.60 488. 3.48 13.83 0.112 2.000 0.293 5.63 19.25 1.64 41.3 1370.6 SAND 2.39 810. 2.20 3.90 40. 0.51 7.32 0.132 1.700 0.306 2.32 7.57 1.51 0.341 87.4 SILTY CLAY 2.59 70. 2.30 4.20 47. 0.59 7.23 0.151 1.700 0.320 2.38 7.42 1.49 0.351 102.7 SILTY CLAY 2.79 500. 2.00 4.50 69. 1.02 5.88 0.171 1.700 0.334 1.80 5.38 1.30 136.4 SILT 2.99 595. 2.70 5.30 73. 0.80 7.59 0.190 1.700 0.348 2.79 8.02 1.54 0.405 161.9 CLAYEY SILT 3.19 1010. 3.00 6.10 91. 0.91 8.01 0.210 1.700 0.361 3.15 8.71 1.60 207.4 SILT 3.39 2630. 4.00 20.60 583. 5.25 8.40 0.230 2.000 0.381 2.27 5.95 0.88 43.6 1369.2 SAND 3.59 035. 7.20 26.00 663. 3.05 15.65 0.249 2.000 0.401 9.12 22.76 1.78 43.2 1939.2 SILTY SAND 3.79 2935. 6.40 24.10 623. 3.26 13.10 0.269 2.000 0.420 7.35 17.50 1.56 41.6 1717.0 SILTY SAND 3.99 1850. 5.70 17.90 423. 2.41 11.51 0.289 2.000 0.440 6.92 15.74 1.50 38.3 1112.8 SILTY SAND A. 19 3235. 4.70 9.50 153. 1.00 9.69 0.308 1.800 0.456 5.34 11.71 1.80 377.7 SILT .39 1355. 5.10 9.60 142. 0.85 10.20 0.328 1.800 0.471 5.99 12.70 1.86 0.795 357.9 CLAYEY SILT .59 1065. 4.40 9.40 160. 1. 14 8.34 0.34 7 1.800 0.487 4.53 9.28 1.64 372.0 SILT 79 830. 4.40 9 /.II 160 1.14 0.04 0.36 7 l. nnn 0.503 4.41 8.77 1.60 366.2 SILT 4.90 1665, 3.00 11 40 755 7.73 6 33 0 38 7 1.900 0.470 7.. 63 4. (13 (1.85 39.7. 530.5 SILTY SAND 5.19 1 760. 3.70 13.60 339. 3. 19 5.69 0.406 1.900 0.538 2.14 3.97 0.75 39.9 680.9 SILTY SAND 5.39 1185. 2.90 7.10 131. 1.50 4.58 0.47.6 1.700 0.552 1.78 3.22 0.70 37.3 228.8 SANDY SILT 5.59 1000. 2.50 6.00 106. 1.42 3.78 0.446 1.700 0.565 1.43 2.52 0.64 36.4 164.4 SANDY SILT END OF SOUNDING 409 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 2 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED, MARCH 80) K0 IN SANDS DETERMINED USING SCHMERIMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: SR 26B (GILCHRIST CO.) TEST SITE #1.5 PERFORMED DATE: 11-05-85 BY: JLD/DGB/KBT CALIBRATION INFORMATION: DELTA A 0.28 BARS DELTA B 0.32 BARS ROD DIA.= A.80 CM FR.RED.DIA.= 3.70 CM 1 BAR = 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI z THRUST A B ED ID KD UO GAAMA (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) ***** ****** ***** ***** ***** 1 ***** ***** ****** ****** 0.68 3900. 7.10 35.80 1024. 4.98 44.55 0.000 2.000 0.88 4740. 16.30 40.00 842. 1.58 88.25 0.000 2.100 1.08 3580. 10.20 32.80 802. 2.48 43.69 0.003 2.150 1.28 2070. 4.50 18.00 470. 3.33 17.43 0.023 2.000 1.A8 1045. 2.80 8.10 171. 1.79 11.06 0.042 1.800 1.68 235. 2.40 4.70 62. 0.72 9.46 0.062 1.700 2.08 785. 0.70 3.50 80. 3.21 2.48 0.101 1.700 2.28 1615. 5.40 16.40 379. 2.19 16.11 0.121 2.000 2.A8 660. 1.90 3.20 26. 0.38 6.08 0.140 1.600 2.88 430. 2.50 4.50 51. 0.59 7.15 0.180 1.700 3.08 490. 2.40 4.70 62. 0.76 6.50 0.199 1.700 3.48 1925. 3.60 9.30 186. 1.60 8.55 0.238 1.800 3.71 1600. 3.60 6.40 80. 0.67 8.50 0.261 1.700 3.88 1145. 3.40 6.20 80. 0.71 7.74 0.278 1.700 4.28 800. 3.60 7.30 113. 0.97 7.49 0.317 1.800 4.48 875. 4.10 8.40 135. 1.02 8.21 0.337 1.800 4.71 730. 3.90 7.40 106. 0.84 7.52 0.359 1.800 4.88 1160. 3.70 7.90 131. 1.12 6.81 0.376 1.800 5.48 1130. 3.70 7.80 128. 1.11 6.12 0.435 1.800 GAGE 0 0.05 BARS GOT DEPTH- 1.05 M ROD WT. 6.50 KG/M DELTA/PHI- 0.50 BLADE T-13.70 tM ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 SV PC OCR KO CU PHI M SOIL TYPE (BAR) (BAR) (BAR) (DEG) (BAR) ****** ***** ***** ***** ***** ***** ****** ************ 0.133 20.97 ***** 5.01 44.9 4007.7 SAND 0.174 ***** ***** 10.66 38.9 3839.3 SANDY SILT 0.213 40.41 ***** 5.25 40.4 3123.0 SILTY SAND 0.233 6.97 29.90 2.05 41.4 1422.2 SAND 0.249 3.58 14.38 1.43 37.8 444.5 SANDY SILT 0.263 2.96 11.29 1.78 0.403 151.3 CLAYEY SILT 0.290 0.22 0.74 0.32 40.2 103.3 SILTY SAND 0.310 9.33 30.12 2.05 37.6 1118.4 SILTY SAND 0.321 1.82 5.67 1.33 0.284 50.8 SILTY CLAY 0.347 2.53 7.30 1.48 0.375 110.0 SILTY CLAY 0.361 2.27 6.29 1.39 0.347 127.8 CLAYEY SILT 0.390 3.03 7.77 1.04 40.9 436.7 SANDY SILT 0.407 3.89 9.55 1.66 0.546 187.1 CLAYEY SILT 0.419 3.46 8.26 1.56 0.500 179.5 CLAYEY SILT 0.448 3.52 7.85 1.53 249.7 SILT 0.464 4.20 9.05 1.62 310.5 SILT 0.482 3.81 7.90 1.53 0.555 233.8 CLAYEY SILT 0.495 3.35 6.77 1.44 278.0 SILT 0.542 3.11 5.73 1.34 256.7 SILT END OF SOUNDING 410 UNIV. OF FLORIDA CIVIL ENG. DEFT.- DR. B.E. RUTH TEST NO. 1 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 1 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE.J-GED,MARCH 80) KO IN SANDS DETERMINED USING SCEMERIMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) ffll ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: SR 26C (GILCHRIST CO.) TEST SITE #4.0 PERFORMED DATE: 11-05-85 BY: JLD/DGB/KBT CALIBRATION INFORMATION: DELTA A 0.28 BARS DELTA B 0.32 BARS GAGE 0 = 0.05 BARS GWI DEPTH- 1.05 M ROD DIA.= 4.80 CM FR.RED.DIA.- 3.70 CM ROD WT.= 6.50 KG/M DELTA/FHI= 0.50 BLADE 1=13.70 FM 1 BAR 1.019 KG/CM2 1.044 TSF = 14.51 PSI z THRUST A B ED ID KD UO GAFMA (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) ***** ****** ***** ***** ***** ***** ***** ****** ****** 0.58 4150. 8.20 34.20 925. 3.72 63.93 0.000 2.150 0.78 3290. 6.80 26.00 678. 3.20 40.33 0.000 2.000 0.98 1360. 4.60 13.40 299. 1.95 23.44 0.000 1.900 1.18 860. 1.30 7.40 200. 4.65 5.88 0.013 1.800 1.38 1745. 2.20 11.80 328. 4.85 8.51 0.032 1.900 1.58 2030. 3.80 15.20 393. 3.30 13.95 0.052 1.900 1.78 1045. 2.60 11.20 291. 3.56 8.93 0.072 1.900 1.98 1180. 2.60 9.40 226. 2.68 8.62 0.091 1.900 2.18 1600. 2.60 9.50 230. 2.75 8.03 0.111 1.900 2.38 1680. 1.60 9.30 259. 5.54 4.27 0.131 1.800 2.58 1370. 1.90 8.40 215. 3.68 5.09 0.150 1.800 2.78 1040. 1.40 7.20 189. 4.55 3.46 0.170 1.800 2.98 1050. 1.50 8.60 237. 5.61 3.36 0.189 1.800 3.18 1115. 1.20 6.20 160. 4.62 2.65 0.209 1.800 3.38 985. 1.30 5.80 142. 3.70 2.81 0.229 1.800 3.58 1125. 1.40 6.70 171. 4.30 2.80 0.248 1.800 3.78 1325. 1.40 7.70 208. 5.56 2.53 0.268 1.800 3.98 1855. 2.00 9.20 240. 4.30 3.66 0.288 1.800 4.18 2540. 2.40 11.30 302. 4.57 4.16 0.307 1.900 4.38 3440. 2.80 13.00 350. 4.53 4.67 0.327 1.900 4.58 7640. 7.80 32.40 874. 3.89 13.08 0.346 2.000 ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 SV PC OCR KO CU PHI M SOIL TYPE (BAR) (BAR) (BAR) (DEG) (BAR) ****** ***** ***** ***** ***** ***** kirftirtrk *r**r*n***r*r**r* 0.112 36.02 ***** 7.36 44.6 3939.1 SAND 0.151 21.65 ***** 4.68 43.0 2589.0 SILTY SAND 0.189 11.56 61.33 2.92 37.4 987.9 SILTY SAND 0.211 0.75 3.58 0.69 40.5 408.7 SAND 0.229 1.20 5.26 0.81 44.0 773.9 SAND 0.246 4.59 18.61 1.60 42.0 1107.8 SILTY SAND 0.264 2.47 9.35 1.15 38.5 700.0 SAND 0.282 2.39 8.48 1.09 39.2 534.9 SILTY SAND 0.299 1.90 6.36 0.93 41.6 529.3 SILTY SAND 0.315 0.26 0.83 0.30 44.4 455.3 SAND 0.331 0.84 2.54 0.58 41.6 411.4 SAND 0.347 0.49 1.42 0.44 40.3 299.2 SAND 0.362 0.50 1.38 0.44 40.2 367.5 SAND 0.378 0.29 0.76 0.32 41.1 215.8 SAND 0.394 0.44 1.11 0.40 39.6 198.6 SAND 0.409 0.40 0.98 0.37 40.4 238.8 SAND 0.425 0.26 0.61 0.28 41.8 271.6 SAND 0.441 0.42 0.95 0.34 43.2 391.1 SAND 0.458 0.30 0.65 0.27 45.2 525.8 SAND 0.476 643.1 SAND 0.496 4.85 9.78 1.10 47.4 2408.3 SAND END OF SOUNDING 411 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 2 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED,MARCH 80) KO IN SANDS DETERMINED USING SCEMERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: >SR 26C (GILCHRIST CO.) TEST SITE #4.5 PERFORMED DATE: 11-05-85 BY: JLD/DGB/KBT CALIBRATION INFORMATION: DELTA A = 0.28 BARS DELTA B = 0.32 BARS ROD DIA.- 4.80 CM FR.RED.DIA.- 3.70 CM GAGE 0 = 0.05 BARS GMT DEPTH- 1.05 M ROD WT.= 6.50 KG/M DELTA/PHI- 0.50 BLADE T-13.70 Ml 1 BAR = 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 z THRUST A B ED ID KD UO GAM1A SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/K3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.58 5375. 3.60 31.60 998. 11.70 21.96 0.000 2.000 0.112 3239.5 SAND 0.78 4528. 10.30 35.20 885. 2.74 60.41 0.000 2.150 0.154 49.57 ***** 7.13 42.5 3721.0 SILTY SAND 0.98 2095. 6.10 19.80 477. 2.42 29.34 0.000 2.000 0.193 17.18 88.81 3.55 39.5 1679.6 SILTY SAND 1.18 1060. 2.60 10.20 255. 2.98 11.32 0.013 1.900 0.218 3.11 14.27 1.42 38.8 667.5 SILTY SAND 1.38 1045. 2.40 9.80 248. 3.16 9.58 0.032 1.900 0.236 2.44 10.34 1.21 39.0 610.2 SILTY SAND 1.58 1095. 2.50 10.00 251. 3.11 9.21 0.052 1.900 0.253 2.44 9.62 1.16 39.0 610.5 SILTY SAND 1.78 820. 2.00 8.40 211. 3.26 6.95 0.072 1.800 0.269 1.66 6.16 0.95 37.5 461.4 SILTY SAND 1.98 900. 1.80 7.70 193. 3.32 5.88 0.091 1.800 0.285 1.22 4.30 0.78 38.6 393.7 SAND 2.18 1110. 1.70 8.40 222. 4.23 5.04 0.111 1.800 0.300 0.83 2.75 0.61 40.6 423.4 SAND 2.38 1280. 2.20 10.10 266. 3.96 6.08 0.131 1.900 0.318 1.27 4.00 0.74 40.6 550.0 SAND 2.98 1370. 2.00 10.00 270. 4.65 4.50 0.189 1.900 0.371 0.78 2.11 0.53 41.2 487.2 SAND 3.18 2715. 4.00 17.20 459. 3.90 8.72 0.209 1.900 0.389 2.54 6.52 0.92 43.5 1093.2 SAND 3.78 3735. 6.00 22.60 583. 3.25 11.61 0.268 2.000 0.445 5.38 12.09 1.27 43.6 1539.7 SILTY SAND 4.18 6125. 9.00 28.80 700. 2.53 16.35 0.307 2.150 0.487 11.17 22.94 1.78 44.8 2074.7 SILTY SAND 4.38 7615. 13.40 38.70 900. 2.15 23.69 0.327 2.150 0.509 26.16 51.35 2.72 44.0 2984.7 SILTY SAND 4.58 8700. 14.20 40.00 918. 2.06 24.10 0.346 2.150 0.532 27.60 51.89 2.74 44.5 3060.2 SILTY SAND END OF SOUNDING 412 UNIV. OF FLORIDA CIVIL ENG. DEPT. DR. B.E. RUTH TEST NO. 1 FILE NAME: PAVEKENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 1 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED,MARCH 80) KO IN SANDS DETERMINED USING SCEMERIMANN METHOD (1983) ESI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGH'S EXPRESSION (ASCE.J-GED.NOV 78) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE,J-GED. JUNE 82) LOCATION: US 301 (ALACHUA CO.) TEST SITE #2.0 PERFORMED DATE: 02-18-85 BY: JLD/DGB/KBT CALIBRATION INFORMATION: DELTA A 0.22 BARS DELTA B 0.37 BARS GAGE 0 0.05 BARS GOT DEPTH- 1.14 M ROD DIA.- 4.80 CM FR.RED.DIA.- 3.70 CM ROD WT.- 6.50 KG/M DELTA/PHI- 0.50 BLADE T-13.70 tfi 1 EAR 1.019 KG/CM2 - 1.044 TSF - 14.51 PSI ANALYSIS USES 320 UNIT WEIGHT - 1.000 T/M3 z THRUST A B ED ID KD UQ GAM4A SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) CT/K3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ...** ***** ***** ***** ***** ****** ************ 0.50 1180. 3.20 14.20 379. 3.84 29.08 0.000 1.900 0.098 7.91 80.67 3.43 40.6 1331.5 SAND 0.70 2760. 2.60 19.70 602. 8.92 14.37 0.000 1.900 0.135 1710.4 SAND 0.90 1595. 4.40 15.00 365. 2.58 23.31 0.000 2.000 0.175 9.78 56.05 2.82 39.6 1204.1 SILTY SAND 1.10 575. 0.70 3.20 70. 2.59 3.73 0.000 1.700 0.208 0.37 1.76 0.50 38.9 112.4 SILTY SAND 1.30 265. 0.40 2.30 48. 2.81 2.17 0.016 1.700 0.22S 0.29 1.31 0.48 33.1 55.0 SILTY SAND 1.50 325. 0.40 3.60 95. 6.78 1.69 0.035 1.700 0.239 0.20 0.85 0.38 35.1 90.3 SAND 1.70 440. 0.30 4.60 117. 4.47 2.98 0.055 1.700 0.253 0.42 1.68 0.52 35.8 169.5 SAND 1.90 440. 0.70 4.10 102. 4.51 2.45 0.075 1.700 0.267 0.34 1.27 0.45 36.0 131.1 SAND 2.10 680. 1.10 6.00 157. 4.71 3.40 0.094 1.300 0.282 0.48 1.68 0.50 38.3 245.4 SAND 2.30 750. 1.10 6.70 183. 5.81 3.04 0.114 1.800 0.298 0.38 1.29 0.43 39.1 267.4 SAND 2.50 1020. 2.50 9.20 223. 2.88 7.06 0.133 1.900 0.316 1.97 6.24 0.95 38.1 488.7 SILTY SAND 2.70 1450. 3.60 10.10 215. 1.87 9.96 0.153 1.900 0.334 3.81 11.42 1.27 39.0 537.5 SILTY SAND 2.90 2380. 7.30 19.60 427. 1.83 19.01 0.173 2.000 0.353 14.12 39.98 2.37 38.9 1326.0 SILTY SAND 3.10 2795. 7.20 17.80 365. 1.57 17.96 0.192 1.950 0.372 12.72 34.21 2.19 40.2 1114.0 SANDY SILT 3.30 2290. 7.30 17.80 361. 1.54 17.32 0.212 1.950 0.390 13.31 34.08 2.18 38.5 1090.4 SANDY SILT 3.50 1910. 9.20 19.40 350. 1.17 21.16 0.232 1.950 0.409 16.22 39.66 2.87 1123.9 SILT 3.70 1680. 12.10 21.90 336. 0.84 26.84 0.251 2.100 0.431 24.74 57.44 3.28 2.433 1152.6 CLAYEY SILT 3.90 1615. 7.20 16.40 314. 1.36 14.84 0.271 1.950 0.449 12.78 28.45 1.99 35.1 901.5 SANDY SILT 4.10 1335. 7.80 14.40 219. 0.86 15.77 0.290 1.950 0.468 11.73 25.06 2.42 1.360 641.8 CLAYEY SILT 4.30 2475. 10.80 18.70 266. 0.75 21.16 0.310 1.950 0.487 19.29 39.63 2.87 2.042 854.8 CLAYEY SILT 4.50 3660. 7.60 25.80 642. 2.82 12.96 0.330 2.000 0.506 8.54 16.87 1.53 42.1 1761.4 SILTY SAND 4.70 5435. 15.60 37.80 787. 1.58 27.17 0.349 2.100 0.528 40.98 77.64 3.31 40.6 2713.4 SANDY SILT 4.90 2910. 9.70 23.80 492. 1.61 16.15 0.369 1.950 0.546 16.51 30.21 2.06 38.5 1454.0 SANDY SILT 5.10 2190. 9.10 21.80 441. 1.54 14.64 0.389 1.950 0.565 15.26 26.99 1.94 36.3 1262.4 SANDY SILT 5.30 2805. 7.80 26.00 642. 2.77 11.43 0.408 2.000 0.585 8.69 14.87 1.45 39.8 1685.0 SILTY SAND 5.50 2740. 3.00 16.20 277. 1.09 12.20 0.428 1.950 0.603 10.13 16.79 2.08 745.4 SILT 5.70 2025. 10.40 18.70 281. 0.83 15.65 0.447 1.950 0.622 15.41 24.77 2.41 1.791 821.5 CLAYEY SILT 5.90 2115. 7.80 19.40 401. 1.66 10.85 0.467 1.950 0.641 9.65 15.06 1.47 37.0 1033.9 SANDY SILT 6.10 2565. 7.40 20.80 467. 2.09 9.76 0.487 2.000 0.660 7.56 11.45 1.28 39.1 1156.2 SILTY SAND 6.30 2855. 5.50 18.60 456. 2.89 6.67 0.506 2.000 0.680 3.32 4.88 0.82 41.5 978.2 SILTY SAND 6.50 3280. 7.10 21.80 514. 2.45 8.63 0.526 2.000 0.700 5.72 8.18 1.07 41.3 1216.8 SILTY SAND END OF SOUNDING 413 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 2 FILE NAME: PAVEMENT-SUBGHADE MATERIALS CHARACTERIZATION FILS NUMBER: 245-D51 RECORD OF DILAICHETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE.J-GED,MARCH 80) KO IN SANDS DETERMINED USING SCHMERTMANN METHOD (1983) HI ANGLE CALCULATION 3ASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) rHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE.J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE,J-GED, JUNE 82) LOCATION: US 301 (ALACHUA CO.) TEST SIIE #3.0 PERFORMED DATE: 02-18-85 BY: JLD/DGB/KBT CALIBRATION INFORMATION: DELTA A 0.22 BARS DELTA B 0.37 BARS GAGE 0 0.05 BARS GWT DEPTH- 1.14 M ROD DIA.- 4.80 CM FR.RED.DIA.- 3.70 at ROD WT.- 6.50 KG/M DELTA/PHI- 0.50 BLADE T-13.70 MM 1 BAR 1.019 KG/CM2 - 1.044 TSF - 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 Z THRUST A B ED ID KD UO GAMMA SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.50 2500. 5.20 26.60 758. 5.05 44.18 0.000 2.000 0.098 2962.0 SAND 0.70 4405. 8.20 30.20 780. 3.08 53.18 0.000 2.000 0.137 31.71 ***** 6.12 44.2 3184.4 SILTY SAND 0.90 2945. 9.00 25.30 572. 1.97 47.50 0.000 2.000 0.177 40.18 ***** 5.73 39.6 2275.4 SILTY SAND 1.10 1335. 2.70 10.20 252. 2.37 11.81 0.000 1.900 0.214 3.02 14.13 1.40 40.7 669.0 SILTY SAND 1.30 800. 1.00 5.20 132. 3.89 4.17 0.016 1.800 0.233 0.43 1.84 0.50 40.5 228.9 SAND 1.50 1240. 1.90 9.20 244. 4.15 6.82 0.035 1.800 0.249 1.10 4.41 0.76 41.6 529.9 SAND 1.70 930. 2.20 8.20 197. 2.78 7.66 0.055 1.900 0.267 1.90 7.13 1.01 36.2 446.5 SILTY SAND 1.90 730. 1.00 4.50 106. 3.22 3.39 0.075 1.700 0.281 0.44 1.56 0.47 39.0 165.3 SILTY SAND 2.10 740. 0.90 4.30 121. 4.29 2.75 0.094 1.700 0.294 0.31 1.05 0.38 39.4 166.4 ' SAND 2.30 655. 0.90 5.00 128. 4.72 2.53 0.114 1.700 0.308 0.33 1.08 0.40 38.2 167.3 SAND 2.70 1220. 5.60 10.80 168. 0.90 15.96 0.153 1.800 0.337 8.62 25.54 2.44 0.996 494.3 CLAYEY SILT 3.10 1765. 11.20 19.80 292. 0.78 28.99 0.192 1.950 0.372 24.08 64.78 3.42 2.313 1023.7 CLAYEY SILT 3.50 1620. 11.70 20.60 303. 0.78 27.43 0.232 1.950 0.409 24.32 59.45 3.32 2.376 1046.2 CLAYEY SILT 3.70 1770. 11.80 21.50 332. 0.85 26.15 0.251 2.100 0.431 23.76 55.17 3.23 2.356 1131.9 CLAYEY SILT 4.10 3640. 11.60 13.20 219. 0.56 23.79 0.290 1.900 0.470 22.36 47.59 3.07 2.284 727.1 SILTY CLAY 4.50 3640. 10.40 32.80 795. 2.50 17.93 0.330 2.150 0.510 17.72 34.73 2.21 40.2 2426.1 SILTY SAND' 4.70 2575. 10.40 17.80 248. 0.72 18.68 0.349 1.950 0.529 17.27 32.65 2.67 1.900 767.1 CLAYEY SILT 4.90 2390. 10.20 30.40 714. 2.28 16.36 0.369 2.150 0.551 18.27 33.13 2.14 36.6 2119.2 SILTY SAND 5.10 3035. 5.80 14.00 277. 1.54 9.12 0.339 1.950 0.570 4.96 8.70 1.09 41.7 668.7 SANDY SILT 5.50 3810. 10.20 30.30 711. 2.28 14.67 0.428 2.150 0.611 14.30 23.40 1.81 40.6 2035.0 SILTY SAND 5.90 2025. 7.20 21.50 500. 2.32 9.51 0.467 2.000 0.653 7.66 11.72 1.31 37.2 1226.1 SILTY SAND 6.30 2705. 5.00 18.20 459. 3.28 5.82 0.506 2.000 0.693 2.60 3.75 0.72 41.5 932.3 SILTY SAND END OF SOUNDING TEST HO. 3 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILAICMETER TEST NO. 3 USING DATA REDUCTION PROCEDURES IN MARCHETTI CASCE.J-GED.MARCH 30) KO IN SANDS DETERMINED USING SC33-RIMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CCNF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED, JUNE 32) LOCATION: US 301 (ALACHUA CO.) TEST SITE #4.0 PERFORMED DATE: 02-18-85 BY: JLD/DG3/KBT CALIBRATION INFORMATION: DELTA A 0.22 BARS DELTA B 0.37 BARS GAGE 0 0.05 BARS GOT DEPTH- 1.14 M ROD DIA.- 4.80 CM FR.RED.DIA.- 3.70 CM ROD WT.- 6.50 KG/M DELTA/FHI- 0.50 BLADE T-13.70 Ml 1 BAR 1.019 KG/CM2 - 1.044 TSF - 14.51 PSI. ANALYSIS USES H20 UNIT WEIGHT - 1.000 T/M3 Z THRUST A B ED ID KD UO GAMA SV PC OCR KO OJ PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** **** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.50 2270. 3.40 22.60 678. 7.40 26.93 0.000 1.900 0.098 2331.2 SAND 0.70 5660. 11.80 40.00 1006. 2.74 75.53 0.000 2.150 0.140 66.10 ***** 3.83 43.5 4440.7 SILTY SAND 0.90 3910. 13.50 38.60 893. 2.07 68.23 0.000 2.150 0.182 87.45 ..... 8.25 38.9 3856.1 SILTY SAND 1.10 1790. 3.00 10.70 259. 2.65 12.81 0.000 1.900 0.220 3.30 15.03 1.43 42.5 708.4 SILTY SAND 1.30 1920. 2.30 11.80 325. 4.66 8.33 0.016 1.900 0.241 1.10 4.54 0.74 44.6 759.9 SAND 1.50 2605. 5.30 18.40 456. 2.73 18.43 0.035 2.000 0.261 8.53 32.71 2.15 42.0 1403.4 SILTY SAND 1.70 1800. 3.80 14.60 372. 3.15 12.22 0.055 1.900 0.279 4.25 15.26 1.45 41.0 1000.7 SILTY SAND 1.90 700. 1.80 5.80 124. 2.08 5.86 0.075 1.800 0.294 1.44 4.89 0.86 36.2 249.0 SILTY SAND 2.30 860. 1.90 8.60 223. 3.89 5.07 0.114 1.800 0.326 1.14 3.51 0.72 37.9 425.1 SAND 2.70 3310. 6.30 18.60 427. 2.15 15.88 0.153 2.000 0.361 8.78 24.31 1.84 42.4 1253.4 SILTY SAND 3.10 2305. 9.00 18.20 314. 1.06 21.41 0.192 1.950 0.399 16.12 40.37 2.89 1010.3 SILT 3.30 2335. 9.40 19.40 343. 1.11 21.27 0.212 1.950 0.418 16.70 39.96 2.88 1102.1 SILT 3.70 2005. 8.60 16.40 263. 0.93 17.92 0.251 1.950 0.455 13.93 30.60 2.61 801.8 SILT 3.90 1490. 7.80 13.60 190. 0.74 15.70 0.271 1.950 0.474 11.79 24.88 2.41 1.370 555.6 CLAYEY SILT 4.30 1325. 8.50 14.40 193. 0.69 15.84 0.310 1.950 0.511 12.39 25.22 2.43 1.494 567.9 CLAYEY SILT 4.70 1740. 7.60 17.40 336. 1.39 12.69 0.349 1.950 0.548 11.62 21.18 1.73 35.3 914.6 SANDY SILT 4.90 2415. 6.70 21.80 529. 2.54 10.17 0.369 2.000 0.568 6.87 12.09 1.31 39.4 1330.0 SILTY SAND 5.30 1655. 11.60 19.00 248. 0.65 18.18 0.408 1.950 0.606 18.96 31.28 2.63 2.105 760.7 CLAYEY SILT 5.70 4200. 10.40 29.00 656. 2.05 14.24 0.447 2.150 0.648 14.03 21.66 1.74 41.1 1860.1 SILTY SAND 5.90 1980. 11.20 17.40 204. 0.55 15.97 0.467 1.900 0.665 17.00 25.55 2.44 1.964 601.6 SILTY CLAY 6.10 2070. 7.30 19.00 405. 1.81 9.39 0.487 2.000 0.685 7.87 11.50 1.30 37.2 987.7 SILTY SAND 6.30 2625. 6.40 19.60 459. 2.44 7.71 0.506 2.000 0.704 5.01 7.10 1.01 40.0 1040.6 SILTY SAND END OF SOUNDING 415 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. 3.E. RUTH TEST NO. 1 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILS NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 1 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE, J-GED, MARCH 80) KO IN SANDS DETERMINED USING SCMRIKANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL CASCE.RALEIGH ODNF.JUNE 75) HI ANGLE NORMALIZED 10 2.72 SARS USING SALIGHS EXPRESSION (ASCE,J-GED.NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE, J-GED, JUNE 82) LOCATION: US 4*1 (COLUMBIA CO.) TEST SITE #4.0 PERFORMED DATE: 02-26-35 BY: DR. DAVIDSON AND BADU-TWENE3CAH CALIBRATION INFORMATION: DELTA A 0.16 BARS DELTA B 0.16 BARS GAGE 0 0.05 BARS GWT DEPTH-10.00 M ROD DU.- 4.30 CM FR.RED.DU.- 3.70 CM ROD WT. 3.50 KG/M DELTA/EHI- 0.50 BLADE T-13.70 W 1 BAR 1.019 KG/CM2 - 1.044 TSF 14.51 PSI ANALYSIS USES H20 UNIT HEIGHT - 1.000 T/M3 Z THRUST A B ED ID KD uo GANKA SV PC OCR KO OJ PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (D EG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** 0.50 3435. 8.50 30.80 801. 3.07 77.43 0.000 2.150 0.097 48.20 ***** 9.11 42.9 3554.0 SILTY SAND 0.70 4215. 11.40 36.70 910. 2.56 73.72 0.000 2.150 0.139 68.87 ***** 8.79 41.3 3996.7 SILTY SAND 0.90 3175. 6.80 21.50 528. 2.46 34.66 0.000 2.000 0.178 19.61 ***** 4.05 42.4 1939.9 SILTY SAND 1.10 1990. 4.00 13.40 331. 2.61 16.95 0.000 1.900 0.216 5.94 27.51 1.96 41.8 992.3 SILTY SAND 1.30 1445. 2.70 10.00 254. 2.98 9.73 0.000 1.900 0.253 2.40 9.49 1.14 41.1 629.6 SILTY SAND 1.50 1345. 2.40 9.20 236. 3.11 7.53 0.000 1.900 0.290 1.72 5.92 0.90 40.8 532.1 SILTY SAND 1.70 1270. 2.20 9.00 236. 3.43 6.06 0.000 1.900 0.328 1.33 4.05 0.75 40.4 487.6 SAND 1.90 1415. 2.40 9.60 251. 3.34 5.94 0.000 1.900 0.365 1.41 3.87 0.73 40.6 513.1 SAND 2.10 1465. 2.60 9.50 240. 2.90 5.92 0.000 1.900 0.402 1.62 4.03 0.75 40.3 489.4 SILTY SAND 2.30 1730. 2.60 10.30 269. 3.31 5.33 0.000 1.900 0.439 1.31 2.99 0.63 41.4 525.1 SAND 2.50 1990. 3.00 11.60 302. 3.22 5.65 0.000 1.900 0.477 1.57 3.29 0.86 41.7 604.8 SILTY SAND 2.70 2130. 3.00 12.20 324. 3.50 5.19 0.000 1.900 0.514 1.38 2.68 0.60 42.1 624.3 SAND 2.90 2515. 4.30 14.70 367. 2.71 7.08 0.000 1.900 0.551 2.91 5.28 0.85 41.7 805.8 SILTY SAND 3.10 1890. 4.40 12.80 294. 2.07 6.98 0.000 1.900 0.589 3.61 6.13 0.94 39.0 637.4 SILTY SAND 3.30 1575. 3.00 8.40 185. 1.87 4.56 0.000 1.900 0.626 1.85 2.96 0.66 38.8 325.9 SILTY SAND 3.50 2085. 2.20 10.80 302. 4.59 2.86 0.000 1.900 0.663 0.56 0.84 0.33 42.1 426.1 SAND 3.70 3085. 4.20 15.70 407. 3.13 5.35 0.000 1.900 0.701 1.93 2.76 0.60 42.8 797.3 SILTY SAND 3.90 4245. 7.80 26.00 651. 2.68 9.48 0.000 2.000 0.740 6.78 9.16 1.12 42.5 1597.9 SILTY SAND 4.10 2550. 5.50 15.10 338. 1.89 6.61 0.000 2.000 0.779 4.24 5.45 0.89 39.3 713.4 SILTY SAND 4.30 1825. 3.10 7.80 160. 1.54 3.67 0.000 1.800 0.814 1.71 2.10 0.56 39.0 244.9 SANDY SILT 4.50 18*0. 3.00 9.30 218. 2.23 3.30 0.000 1.900 0.852 1.51 1.77 0.52 39.1 322.9 SILTY SAND 4.70 1875. 2.80 11.20 294. 3.39 2.82 0.000 1.900 0.889 1.20 1.35 0.45 39.4 412.2 SAND 4.90 2135. 3.00 12.00 316. 3.41 2.89 0.000 1.900 0.926 1.21 1.31 0.44 40.1 449.6 SAND 5.10 2420. 3.80 14.20 367. 3.11 3.53 0.000 1.900 0.964 1.73 1.80 0.51 40.3 586.4 SILTY SAND 5.30 2340. 4.00 15.00 389. 3.14 3.57 0.000 1.900 1.001 1.94 1.94 0.54 39.7 625.0 SILTY SAND 5.50 2085. 3.70 11.40 269. 2.25 3.31 0.000 1.900 1.038 1.95 1.88 0.54 38.8 399.9 SILTY SAND 5.70 1865. 3.00 11.00 280. 2.96 2.53 0.000 1.900 1.075 1.42 1.32 0.46 38.4 364.9 SILTY SAND 5.90 1925. 3.60 14.00 367. 3.30 2.88 0.000 1.900 1.113 1.81 1.63 0.51 38.0 521.2 SAND 6.10 2470. 3.50 13.00 334. 3.06 2.74 0.000 1.900 1.150 1.45 1.27 0.44 40.0 460.1 SILTY SAND 6.30 2495. 3.90 14.40 371. 3.05 2.95 0.000 1.900 1.187 1.75 1.47 0.47 39.7 533.8 SILTY SAND 6.50 2410. 3.80 14.00 360. 3.04 2.79 0.000 1.900 1.225 1.72 1.41 0.47 39.3 500.8 SILTY SAND END OF SOUNDING 416 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 2 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE.J-GED,MARCH 80) KO IN SANDS DETERMINED USING SCEMERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE.RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: US 441 (COLUMBIA CO.) TEST SITE #5.0 PERFORMED DATE: 02-26-85 BY: DR. DAVIDSON AND BADU-IWENEBOAH CALIBRATION INFORMATION: DELTA A 0.16 BARS DELTA B - 0.16 BARS GAGE 0 = 0.05 BARS GWT DEPTH=10 .00 M ROD DIA.- 4.8C 1 CM FR.RED.DIA. .= 3.70 CM RCD WT. = 6.50 KG/M DELTA/FHI= 0. .50 BLADE T=13.70 PM 1 BAR = 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 z THRUST A B ED ID KD UO GAtMA SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ttirttifto ***** ***** . ***** ***** ****** ****** ****** ***** ***** ***** *r*r*r*W ***** ****** ************ 0.50 3655. 4.80 27.30 808. 6.13 39.19 0.000 2.000 0.097 3065.2 SAND 0.70 4390. 9.30 32.30 826. 2.88 59.45 0.000 2.150 0.139 41.72 ***** 6.96 43.3 3460.5 SILTY SAND 0.90 3290. 6.60 21.40 528. 2.54 33.54 0.000 2.000 0.178 18.00 ***** 3.88 42.9 1923.5 SILTY SAND 1.10 2085. 4.00 14.20 360. 2.87 16.76 0.000 1.900 0.216 5.68 26.31 1.92 42.3 1076.0 SILTY SAND 1.30 1580. 2.80 10.40 265. 3.00 10.06 0.000 1.900 0.253 2.48 9.79 1.15 41.7 664.7 SILTY SAND 1.50 1445. 2.20 9.20 243. 3.55 6.81 0.000 1.900 0.290 1.28 4.40 0.76 41.8 527.1 SAND 1.70 1380. 2.00 9.20 251. 4.09 5.39 0.000 1.900 0.328 0.93 2.85 0.61 41.6 492.1 SAND 1.90 1525. 2.20 9.60 258. 3.80 5.36 0.000 1.900 0.365 1.04 2.85 0.61 41.7 505.2 SAND 2.10 1655. 2.60 10.30 269. 3.31 5.82 0.000 1.900 0.402 1.43 3.55 0.69 41.3 545.8 SAND 2.30 1770. 2.80 10.40 265. 3.00 5.79 0.000 1.900 0.439 1.57 3.58 0.70 41.3 537.3 SILTY SAND 2.50 2030. 2.80 10.90 283. 3.24 5.29 0.000 1.900 0.477 1.30 2.73 0.60 42.2 551.8 SILTY SAND 2.70 2130. 2.70 12.20 334. 4.10 4.57 0.000 1.900 0.514 0.99 1.93 0.50 42.6 608.9 SAND 2.90 2405. 4.40 14.40 353. 2.52 7.30 0.000 1.900 0.551 3.20 5.81 0.90 41.2 782.0 SILTY SAND 3.10 2350. 4.40 14.40 353. 2.52 6.84 0.000 1.900 0.589 3.11 5.28 0.86 40.9 761.2 SILTY SAND 3.30 1830. 4.20 9.40 178. 1.26 6.52 0.000 1.800 0.624 3.47 5.56 0.90 38.6 369.7 SANDY SILT 3.50 1565. 4.60 9.00 149. 0.95 6.83 0.000 1.800 0.659 4.48 6.80 1.44 314.9 SILT 3.75 1780. 5.40 13.20 273. 1.53 7.28 0.000 1.950 0.705 5.18 7.35 1.05 36.9 598.0 SANDY SILT 3.90 2115. 4.40 12.20 273. 1.90 5.64 0.000 1.900 0.733 3.07 4.19 0.78 39.3 534.6 SILTY SAND 4.10 2160. 4.20 11.60 258. 1.88 5.13 0.000 1.900 0.771 2.71 3.52 0.72 39.5 483.0 SILTY SAND 4.30 2275. 3.40 13.40 353. 3.36 3.75 0.000 1.900 0.808 1.48 1.83 0.51 40.7 580.9 SAND 4.50 2375. 3.80 13.30 334. 2.79 4.08 0.000 1.900 0.845 1.86 2.20 0.56 40.5 571.9 SILTY SAND 4.70 2210. 3.20 12.00 309. 3.09 3.27 0.000 1.900 0.882 1.36 1.54 0.47 40.3 472.5 SILTY SAND 4.90 2180. 3.20 11.80 302. 3.00 3.15 0.000 1.900 0.920 1.38 1.50 0.47 40.1 451.4 SILTY SAND 5.10 2250. 3.40 11.90 298. 2.77 3.24 0.000 1.900 0.957 1.53 1.60 0.49 40.0 448.3 SILTY SAND 5.30 2430. 3.60 12.80 324. 2.85 3.28 0.000 1.900 0.994 1.58 1.59 0.48 40.3 492.6 SILTY SAND 5.50 2510. 3.80 13.40 338. 2.83 3.34 0.000 1.900 1.032 1.70 1.65 0.49 40.3 519.1 SILTY SAND END OF SOUNDING 417 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 3 FILE NAME: PAVEMENT-SUEGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATOMETER TEST NO. 3 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED,MARCH 80) K0 IN SANDS DETERMINED USING SCMERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE, J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: US 441 (COLUMBIA CO.) TEST SITE #6.0 PERFORMED DATE: 02-26-85 BY: DR. DAVIDSON AND BADU-TWENEBOAH CALIBRATION INFORMATION: DELTA A = 0.16 BARS DELTA B 0.16 BARS GAGE 0 = 0.05 BARS GWT DEPTH=10.00 M ROD DIA.= 4.80 CM FR.RED.DIA.- 3.70 CM ROD WT.= 6.50 KG/M DELTA/PHI= 0.50 BLADE T=13.70 M 1 BAR = 1.019 KG/CM2 = 1.044 TSF 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT 1.000 T/M3 z THRUST A B ED ID KD UO GAt-ttA SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.50 3425. 5.20 27.40 797. 5.45 43.46 0.000 2.000 0.097 3102.0 SAND 0.70 4740. 9.80 34.40 885. 2.93 62.47 0.000 2.150 0.139 45.41 ***** 7.30 43.5 3746.1 SILTY SAND 0.90 3975. 7.70 24.60 604. 2.49 39.12 0.000 2.000 0.178 23.92 ***** 4.52 43.3 2290.4 SILTY SAND 1.10 2585. 4.90 17.20 436. 2.85 20.26 0.000 2.000 0.218 8.20 37.65 2.31 42.7 1383.0 SILTY SAND 1.30 1915. 3.50 12.60 320. 2.91 12.44 0.000 1.900 0.255 3.75 14.72 1.42 42.1 865.8 SILTY SAND 1.50 1675. 2.60 10.60 280. 3.47 7.96 0.000 1.900 0.292 1.71 5.84 0.88 42.3 644.0 SAND 1.70 1490. 2.10 10.00 276. 4.35 5.56 0.000 1.900 0.330 0.94 2.87 0.61 42.0 549.4 SAND 1.90 1500. 2.20 9.30 247. 3.61 5.37 0.000 1.900 0.367 1.07 2.93 0.62 41.5 484.3 SAND 2.10 1200. 1.90 8.00 211. 3.53 4.28 0.000 1.800 0.402 0.92 2.29 0.57 39.8 371.2 SAND 2.30 1160. 1.70 7.00 181. 3.35 3.57 0.000 1.800 0.438 0.75 1.73 0.50 39.6 291.2 SAND 2.50 1650. 1.90 8.90 243. 4.18 3.54 0.000 1.800 0.473 0.58 1.23 0.40 41.9 389.2 SAND 2.70 1995. 2.30 11.00 305. 4.42 3.90 0.000 1.900 0.510 0.69 1.34 0.41 42.6 513.8 SAND 2.90 2635. 3.80 14.20 367. 3.11 6.22 0.000 1.900 0.547 2.02 3.70 0.70 42.6 766.8 SILTY SAND 3.10 3015. 4.20 15.40 396. 3.03 6.44 0.000 1.900 0.585 2.22 3.80 0.70 43.1 839.5 SILTY SAND 3.30 3800. 4.80 17.40 447. 3.00 6.88 0.000 2.000 0.624 2.41 3.86 0.70 44.2 973.5 SILTY SAND 3.50 4725. 7.50 23.40 568. 2.39 10.30 0.000 2.000 0.663 6.56 9.89 1.15 43.6 1435.0 SILTY SAND 3.70 4780. 8.30 28.50 724. 2.81 10.56 0.000 2.000 0.702 7.57 10.78 1.21 43.2 1848.0 SILTY SAND 3.90 4310. 8.20 26.20 644. 2.50 10.01 0.000 2.000 0.742 7.64 10.31 1.19 42.3 1611.1 SILTY SAND 4.10 3995. 7.80 25.20 622. 2.54 9.03 0.000 2.000 0.781 6.78 8.68 1.10 41.9 1499.0 SILTY SAND 4.30 4170. 7.80 24.20 586. 2.38 8.66 0.000 2.000 0.820 6.50 7.92 1.04 42.1 1388.2 SILTY SAND 4.50 4490. 7.40 25.00 630. 2.73 7.73 0.000 2.000 0.860 5.15 5.99 0.90 42.9 1430.5 SILTY SAND 4.70 3925. 6.80 23.70 604. 2.86 6.77 0.000 2.000 0.899 4.42 4.91 0.82 42.2 1303.1 SILTY SAND 4.90 4015. 6.80 22.40 557. 2.61 6.55 0.000 2.000 0.938 4.34 4.63 0.80 42.2 1181.4 SILTY SAND 5.10 4470. 7.80 27.30 699. 2.90 7.11 0.000 2.000 0.977 5.24 5.36 0.86 42.4 1538.7 SILTY SAND 5.30 4025. 6.40 21.80 549. 2.75 5.66 0.000 2.000 1.017 3.55 3.49 0.69 42.3 1097.1 SILTY SAND 5.50 3965. 5.80 21.10 546. 3.05 4.89 0.000 2.000 1.056 2.73 2.58 0.59 42.5 1025.2 SILTY SAND END OF SOUNDING 418 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 1 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 1 USING DATA REDXTION PROCEDURES IN MARCHETTI (ASCE.J-GED,MARCH 80) KO IN SANDS DETERMINED USING SOMERTMANN METHCO (1983) FHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGH'S EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: SR 15A (MARTIN CO.) TEST SITE #3.0 PERFORMED DATE: 04-29-86 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A 0.17 BARS DELTA B 0.35 BARS GAGE 0 0.05 BARS GWT DEPTH- 1.65 M ROD DIA.- 3.70 CM FR.RED.DIA.- 3.70 CM ROD WT.= 6.50 KG/M DELTA/IHI= 0.50 BLADE 1=13.70 Ml 1 BAR = 1.019 KG/CM2 1.044 TSF 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 z THRUST A B ED ID KD UO GAMIA SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) i,**** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.42 5160. 3.30 33.40 1078. 16.00 22.84 0.000 1.900 0.085 3536.9 SAND 0.62 6385. 9.20 34.80 914. 3.26 63.41 0.000 2.150 0.127 3882.5 SILTY SAND 0.82 4230. 8.20 27.50 684. 2.67 44.34 0.000 2.000 0.166 28.14 ***** 5.13 43.6 2675.5 SILTY SAND 1.02 1665. 3.80 13.60 338. 2.82 16.96 0.000 1.900 0.204 5.86 28.77 2.01 40.8 1014.4 SILTY SAND 1.22 550. 2.00 4.60 76. 1.08 8.50 0.000 1.700 0.237 2.27 9.56 1.66 177.2 SILT 1.42 280. 1.00 2.10 21. 0.56 4.06 0.000 1.600 0.269 0.81 3.02 1.00 0.143 33.3 SILTY CLAY 1.62 245. 1.10 1.90 10. 0.24 4.05 0.000 1.500 0.298 0.89 3.00 0.99 0.158 16.0 MUD 1.82 330. 1.00 2.00 17. 0.47 3.45 0.017 1.600 0.313 0.73 2.34 0.88 0.136 24.7 SILTY CLAY 2.02 385. 1.00 1.80 10. 0.27 3.32 0.036 1.500 0.322 0.71 2.20 0.85 0.134 14.0 MUD 2.22 425. 0.50 1.80 28. 1.56 1.57 0.056 1.600 0.334 0.28 0.82 0.38 35.1 24.2 SANDY SILT 2.42 1220. 1.70 9.90 280. 5.93 3.89 0.076 1.800 0.350 0.54 1.56 0.45 41.2 469.9 SAND 2.62 1470. 3.10 11.20 276. 2.90 7.47 0.095 1.900 0.368 2.34 6.37 0.95 39.9 619.9 SILTY SAND 2.82 760. 1.20 5.20 127. 3.54 2.69 0.115 1.800 0.383 0.49 1.29 0.44 37.8 172.4 SAND 3.02 850. 0.80 2.00 25. 0.95 1.90 0.134 1.600 0.395 0.37 0.92 0.52 21.1 SILT 3.22 1255. 0.40 2.20 47. 4.45 0.74 0.154 1.700 0.409 39.6 SAND 3.42 1635. 1.00 6.20 171. 6.90 1.68 0.174 1.800 0.425 161.9 SAND 3.62 6000. 7.20 19.40 426. 1.87 14.73 0.193 2.000 0.444 7.39 16.63 1.49 45.7 1219.9 SILTY SAND END OF SOUNDING 419 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 2 FILE NAME: PAVMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATOMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED,MARCH 80) K0 IN SANDS DETERMINED USING SOWERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE.RALEIGH CONF, JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGH'S EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: SR 15A (MARTIN CO.) TEST SITE #4.0 PERFORMED DATE: 04-29-86 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A = 0.17 BARS DELTA B 0.35 BARS GAGE 0 = 0.05 BARS GWT DEPTH- 1.65 M ROD DIA. 3.70 CM FR.R£D.DIA.= 3.70 CM RCD WT. 6.50 KG/M DELTA/PHI= 0.50 BLADE T=13.70 t-M 1 BAR 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 z THRUST A B ED ID KD UO GAMA SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.73 2910. 5.20 30.20 892. 6.28 28.64 0.000 2.000 0.143 9.28 64.87 3.09 45.0 3118.5 SAND 0.93 2730. 5.90 24.50 659. 3.71 28.07 0.000 2.000 0.182 13.20 72.41 3.25 42.4 2290.6 SAND 1.13 830. 3.20 10.40 243. 2.35 13.60 0.000 1.900 0.220 5.05 23.00 1.80 35.3 679.3 SILTY SAND 1.33 350. 1.00 2.10 21. 0.56 4.35 0.000 1.600 0.251 0.84 3.36 1.05 0.146 34.8 SILTY CLAY 1.53 265. 1.20 2.00 10. 0.23 4.66 0.000 1.500 0.280 1.05 3.74 1.10 0.177 17.5 MUD 1.73 265. 0.90 1.90 17. 0.51 3.25 0.008 1.600 0.304 0.65 2.13 0.84 0.123 23.6 SILTY CLAY 1.93 325. 0.80 1.50 7. 0.21 2.82 0.027 1.500 0.314 0.54 1.71 0.74 0.106 7,9 MUD 2.13 450. 0.50 1.20 7. 0.34 1.74 0.047 1.500 0.324 0.26 0.81 0.47 0.060 5.6 MUD 2.33 1270. 1.30 10.20 305. 9.42 2.75 0.067 1.800 0.339 0.15 0.45 0.23 42.9 421.3 SAND 2.53 2750. 3.70 18.80 531. 5.10 8.42 0.086 1.900 0.357 1.89 5.29 0.82 44.4 1248.6 SAND 2.73 1945. 2.90 13.90 382. 4.60 6.38 0.106 1.900 0.375 1.37 3.66 0.69 42.6 805.6 SAND 2.93 1030. 2.60 8.90 211. 2.63 5.88 0.126 1.900 0.392 1.85 4.73 0.84 37.5 426.6 SILTY SAND 3.13 740. 1.40 3.00 39. 0.86 3.27 0.145 1.600 0.404 0.87 2.15 0.84 0.164 54,0 CLAYEY SILT 3.33 755. 1.20 5.60 141. 4.24 2.29 0.165 1.800 0.420 0.45 1.06 0.41 37.5 172.4 SAND 3.53 1085. 0.40 3.00 76. 9.43 0.53 0.184 1.700 0.433 64.4 SAND 3.73 1800. 0.70 7.40 225. 21.15 0.69 0.204 1.700 0.447 191.4 SAND 3.93 1030. 0.40 2.40 54. 6.99 0.48 0.224 1.700 0.461 0.01 0.02 0.05 41.5 45.8 SAND 4.23 2750. 0.30 0.80 -1. -0.12 0.253 P01 = 0.42 PO - 0.42 PI = 0.40 QUESTIONABLE END OF SOUNDING 420 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 3 FILE NAME: PAVEMENT SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 3 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE.J-GED,MARCH 80) K0 IN SANDS DETERMINED USING SCHMERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE.J-GED,JUNE 82) LOCATION: SR 15A (MARTIN CO.) TEST SITE #5.0 PERFORMED DATE: 04-29-86 BY: DAVE/KHASI/ED CALIBRATION INFORMATION: DELTA A = 0.17 BARS DELTA B 0.35 BARS GAGE 0 = 0.05 BARS GWT DEPTH- 1.65 M ROD DIA.- 3.70 CM FR.RED.DIA.- 3.70 CM ROD WT.- 6.50 KG/M DELTA/PHI- 0.50 BLADE T-13.70 Ml 1 BAR = 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 Z THRUST A B ED ID KD UO GAM4A SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.42 7335. 5.60 27.00 761. 4.69 53.75 0.000 2.000 0.087 3113.2 SAND 0.62 6835. 10.90 32.50 768. 2.22 77.14 0.000 2.150 0.129 55.55 ***** 8.78 46.2 3405.7 SILTY SAND 0.82 3650. 6.90 26.10 681. 3.22 36.13 0.000 2.000 0.168 18.88 ***** 4.13 43.7 2529.2 SILTY SAND 1.02 1670. 5.00 16.20 389. 2.45 22.08 0.000 2.000 0.208 10.79 51.93 2.70 39.0 1264.6 SILTY SAND 1.22 560. 1.00 3.40 68. 1.92 4.26 0.000 1.700 0.241 0.64 2.66 0.63 37.1 116.3 SILTY SAND 1.42 310. 0.80 1.70 14. 0.44 3.31 0.000 1.600 0.272 0.60 2.19 0.85 0.112 18.9 SILTY CLAY 1.62 255. 0.80 1.50 7. 0.21 3.02 0.000 1.500 0.302 0.57 1.90 0.79 0.111 8.3 MUD 1.82 270. 0.80 1.70 14. 0.45 2.79 0.017 1.600 0.317 0.53 1.68 0.74 0.106 16.5 SILTY CLAY 2.02 380. 0.85 1.60 8. 0.26 2.82 0.036 1.500 0.326 0.56 1.71 0.75 0.111 10.1 MUD 2.22 450. 0.40 1.60 25. 1.66 1.27 0.056 1.600 0.338 0.21 0.61 0.32 35.9 21.1 SANDY SILT 2.42 1225. 1.50 11.70 353. 9.58 3.00 0.076 1.800 0.354 0.27 0.77 0.31 42.0 512.5 SAND 2.62 1405. 3.40 12.50 313. 3.01 8.06 0.095 1.900 0.372 2.86 7.71 1.05 39.0 723.0 SILTY SAND 2.82 630. 1.00 2.40 32. 0.96 2.51 0.115 1.600 0.383 0.55 1.42 0.67 35.7 SILT 3.02 1430. 0.60 2.70 58. 3.28 1.28 0.134 1.700 0.397 48.9 SILTY SAND 3.22 5430. 3.60 21.50 633. 6.77 6.50 0.154 1.900 0.415 1346.3 SAND 3.42 5650. 7.00 24.60 622. 2.94 14.02 0.174 2.000 0.434 6.46 14.86 1.40 45.7 1755.1 SILTY SAND 3.62 3165. 2.10 12.40 356. 6.68 3.40 0.193 1.900 0.452 557.1 SAND 3.82 2180. 3.60 14.60 382. 3.69 6.35 0.213 1.900 0.470 1.89 4.02 0.73 42.0 804.0 SAND 4.02 5415. 11.20 40.00 1030. 3.07 19.65 0.233 2.150 0.492 18.29 37.15 2.29 42.9 3234.9 SILTY SAND END OF SOUNDING 421 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 1 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 1 USING DATA REDUCTION ROCEDURES IN MARCHETTI (ASCE.J-GED,MARCH 80) KO IN SANDS DETERMINED USING SOMERTMANN METHOD (1983) IHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE.J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE.J-GED,JUNE 82) LOCATION: SR 15B (MARTIN CO.) TEST SITE #2.0 PERFORMED DATE: 04-29-86 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A = 0.17 BARS DELTA B = 0.35 BARS GAGE 0 0.05 BARS GWT DEPTH= 1.65 M ROD DIA.= 3.70 CM FR.RED.DIA.- 3.70 CM ROD WT. 6.50 KG/M DELTA/PHI- 0.50 BLADE 1=13.70 Ml 1 BAR 1.019 KG/CM2 = 1.044 TSF 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 z THRUST A B ED ID KD UO GAM1A (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) ***** ****** ***** ***** ***** ***** ***** ****** ****** 0.88 4575. 7.20 27.10 706. 3.20 54.28 0.000 2.000 1.08 3450. 6.60 24.60 637. 3.14 37.41 0.000 2.000 1.28 1760. 3.20 12.90 334. 3.37 14.78 0.000 1.900 1.48 600. 2.00 7.80 192. 2.99 8.11 0.000 1.800 1.68 160. 0.40 1.10 7. 0.37 1.99 0.003 1.500 1.88 105. 0.60 1.50 14. 0.59 2.54 0.023 1.600 2.08 260. 0.60 1.80 25. 1.11 2.31 0.042 1.600 2.28 345. 0.60 1.50 14. 0.62 2.20 0.062 1.600 2.48 550. 0.30 1.80 36. 3.55 0.95 0.081 1.700 2.68 2645. 2.30 19.10 593. 11.36 4.67 0.101 1.900 2.88 3845. 5.80 21.60 557. 3.19 14.73 0.121 2.000 3.08 2950. 5.10 18.60 473. 3.08 12.26 0.140 2.000 3.28 1350. 1.80 9.20 251. 5.10 3.76 0.160 1.800 3.48 610. 1.60 4.20 76. 1.52 3.68 0.180 1.700 3.68 775. 0.40 2.50 58. 6.86 0.60 0.199 1.700 3.88 1845. 1.80 10.50 298. 6.65 3.07 0.219 1.800 4.08 2765. 2.00 11.80 338. 6.87 3.25 0.238 1.800 4.28 3830. 5.00 19.60 513. 3.56 9.13 0.258 2.000 4.48 3450. 1.60 12.40 375. 11.63 1.97 0.278 1.800 4.68 2130. 2.20 15.80 477. 10.03 2.80 0.297 1.900 4.88 10000. 6.80 23.60 593. 2.95 11.38 0.317 2.000 SV PC OCR KO CU PHI M SOIL TYPE (BAR) (BAR) (BAR) (DEG) (BAR) ****** ***** ***** ***** ***** ***** ****** ************ 0.117 27.10 ***** 6.17 44.8 2896.1 SILTY SAND 0.156 19.20 ***** 4.32 43.1 2387.8 SILTY SAND 0.194 3.91 20.22 1.67 42.2 959.9 SAND 0.229 2.03 8.89 1.15 35.1 445.9 SILTY SAND 0.255 0.25 0.99 0.54 0.056 5.6 MUD 0.267 0.39 1.45 0.68 0.079 15.2 SILTY CLAY 0.279 0.35 1.25 0.62 25.9 SILT 0.291 0.34 1.16 0.60 0.072 13.2 CLAYEY SILT 0.304 0.08 0.26 0.19 38.7 30.4 SAND 0.322 1090.8 SAND 0.342 6.34 18.56 1.59 44.2 1596.1 SILTY SAND 0.361 5.05 13.98 1.38 42.9 1273.6 SILTY SAND 0.377 0.52 1.38 0.42 41.6 413.4 SAND 0.391 0.99 2.54 0.65 34.8 116.3 SANDY SILT 0.405 0.04 0.10 0.12 39.9 48.9 SAND 0.420 0.16 0.38 0.21 44.1 439.8 SAND 0.436 515.4 SAND 0.456 2.86 6.29 0.89 44.8 1241.8 SAND 0.471 407.8 SAND 0.489 0.11 0.23 0.16 44.6 664.4 SAND 0.509 1555.7 SILTY SAND END OF SOUNDING 422 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 2 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED,MARCH 80) K0 IN SANDS DETERMINED USING SCHMERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL CASCE,RALEIGH CONF,JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: SR 15B (MARTIN CO.) TEST SITE #4.0 PERFORMED DATE: 04-29-86 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A = 0.17 BARS DELTA B 0.35 BARS GAGE 0 = 0.05 BARS GWT DEPTH* 1.65 M ROD DIA.- 3.70 CM FR.RED.DIA.- 3.70 CM ROD WT.- 6.50 KG/M DELTA/PHI- 0.50 BLADE T-13.70 PM 1 BAR 1.019 KG/CM2 1.044 TSF 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 z THRUST A B ED ID KD UO GAtMA SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.51 3300. 1.80 9.60 265. 4.91 15.11 0.000 1.800 0.103 766.7 SAND 0.71 7465. 10.00 37.40 979. 3.22 60.44 0.000 2.150 0.145 35.99 ***** 6.55 47.5 4116.6 SILTY SAND 0.91 6085. 11.80 37.40 914. 2.47 56.92 0.000 2.150 0.187 51.63 ***** 6.65 43.7 3789.0 SILTY SAND 1.11 3310. 6.00 22.20 571. 3.09 23.54 0.000 2.000 0.227 11.17 49.29 2.66 43.4 1891.4 SILTY SAND 1.31 1280. 2.90 12.80 342. 3.86 9.66 0.000 1.900 0.264 2.68 10.14 1.19 39.9 844.3 SAND 1.51 410. 0.40 1.70 28. 1.70 1.63 0.000 1.600 0.295 0.24 0.80 0.37 35.6 24.2 SANDY SILT 1.71 275. 0.70 1.90 25. 0.92 2.43 0.006 1.600 0.321 0.44 1.36 0.65 26.7 SILT 1.91 330. 1.10 2.00 14. 0.34 3.53 0.026 1.600 0.333 0.81 2.43 0.90 0.149 19.9 CLAY 2.11 350. 0.80 1.80 17. 0.59 2.47 0.045 1.600 0.344 0.48 1.39 0.66 0.099 18.7 SILTY CLAY 2.31 475. 0.30 1.80 36. 3.36 0.86 0.065 1.700 0.358 0.14 0.40 0.26 36.5 30.4 SAND 2.51 1770. 1.90 15.30 469. 10.47 3.44 0.084 1.900 0.376 0.17 0.47 0.23 44.3 737.9 SAND 2.71 3710. 4.80 25.40 732. 5.53 9.64 0.104 2.000 0.395 2.55 6.44 0.90 45.3 1805.7 SAND 2.91 3715. 5.60 24.80 681. 4.21 11.23 0.124 2.000 0.415 4.40 10.60 1.18 44.2 1776.4 SAND 3.11 2180. 4.20 17.60 469. 3.83 8.16 0.143 1.900 0.433 2.99 6.91 0.97 41.5 1090.5 SAND 3.31 845. 3.00 8.80 192. 2.06 5.98 0.163 1.900 0.450 2.51 5.58 0.94 34.5 388.9 SILTY SAND 3.51 740. 1.30 2.60 28. 0.68 2.59 0.183 1.600 0.462 0.69 1.50 0.69 0.141 31.9 CLAYEY SILT 3.71 525. 1.30 2.00 7. 0.16 2.56 0.202 1.500 0.472 0.69 1.47 0.69 0.141 7.2 MUD 3.91 1595. 1.50 5.60 130. 3.08 2.50 0.222 1.800 0.488 0.25 0.52 0.25 42.4 169.0 SILTY SAND 4.11 1885. 1.20 6.80 185. 6.47 1.64 0.241 1.800 0.503 171.9 SAND 4.31 1715. 1.30 7.20 196. 6.35 1.71 0.261 1.800 0.519 0.05 0.10 0.10 43.5 189.8 SAND END OF SOUNDING 423 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 3 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 3 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED,MARCH 80) KO IN SANDS DETERMINED USING SCHMERIMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FCR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: SR 15B (MARTIN CO.) TEST SITE #3.0 PERFORMED DATE: 04-29-86 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A 0.17 BARS ROD DIA. 3.70 CM DELTA B FR.RED.DIA. 0.35 BARS 3.70 CM GAGE 0 ROD WT, = 0.05 BARS GWT DEPTH 1.65 M . 6.50 KG/M DELTA/PHI 0.50 BLADE T13.70 M 1 BAR 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 Z THRUST A B ED ID KD UO GAM4A SV PC OCR KO CU PHI M SOIL TYPE (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) ***** ****** ***** ***** ***** ***** ***** ****** ****** ****** ***** ***** ***** ***** ***** ****** ************ 0.37 6765. 3.50 25.80 794. 9.04 32.45 0.000 1.900 0.078 2868.2 SAND 0.57 10000. 12.40 39.40 965. 2.48 93.15 0.000 2.150 0.120 4450.4 SILTY SAND 0.87 5530. 7.20 31.20 855. 4.01 33.90 0.000 2.000 0.181 14.73 81.26 3.51 46.9 3127.6 SAND 0.97 4160. 5.00 24.70 699. 4.84 20.71 0.000 2.000 0.201 5.30 26.39 1.89 47.2 2228.7 SAND 1.17 2285. 3.20 17.10 488. 5.30 11.13 0.000 1.900 0.238 2.17 9.11 1.08 44.6 1268.1 SAND 1.37 735. 1.90 4.20 65. 0.97 7.11 0.000 1.700 0.272 1.96 7.23 1.48 140.0 SILT 1.57 370. 0.90 2.20 28. 0.83 3.24 0.000 1.600 0.303 0.64 2.12 0.84 0.122 38.7 CLAYEY SILT 1.77 315. 0.70 2.20 36. 1.36 2.35 0.012 1.600 0.323 0.52 1.61 0.55 31.7 38.9 SANDY SILT 1.97 325. 0.50 1.80 28. 1.49 1.64 0.031 1.600 0.334 0.35 1.04 0.44 32.7 24.2 SANDY SILT 2.17 430. 0.40 1.80 32. 2.17 1.22 0.051 1.700 0.348 0.22 0.63 0.33 35.4 27.3 SILTY SAND 2.37 1670. 1.50 13.80 429. 12.88 2.64 0.071 1.800 0.364 0.01 0.04 0.06 45.2 576.5 SAND 2.57 4375. 7.90 28.40 728. 3.03 18.07 0.090 2.000 0.383 11.56 30.14 2.06 43.4 2227.9 SILTY SAND 2.77 4500. 5.60 24.70 677. 4.17 11.61 0.110 2.000 0.403 3.87 9.61 1.11 45.6 1788.3 SAND 2.97 3215. 6.40 22.20 557. 2.85 13.31 0.130 2.000 0.423 7.40 17.50 1.56 42.2 1542.6 SILTY SAND 3.17 1395. 2.90 12.40 327. 3.89 5.50 0.149 1.900 0.440 1.66 3.76 0.73 39.5 648.0 SAND 3.37 935. 2.10 6.40 138. 2.13 4.08 0.169 1.800 0.456 1.22 2.67 0.64 37.0 230.2 SILTY SAND 3.57 1365. 2.80 8.80 200. 2.34 5.19 0.188 1.900 0.474 1.67 3.52 0.71 39.0 379.7 SILTY SAND END OF SOUNDING 424 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 1 FILE NAME: PAVFTtENT-SUPGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATOMETER TEST NO. 1 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE.J-GED,MARCH 80) KO IN SANDS DETERMINED USING SCH-1ERTMANN METHOD (1983) nil ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH OOUF.JUNE 75) nil ANGLE NORMALIZED TO 2.72 RARR USING BAUGH'S EXPRESSION (ASCE,J-GED,NOV 78) irUFIED MAYNE AND KUIHAWY FOKMUT.A USED FOR OCR IN SAffllS (ASCE.J-GED,.BINE 87.) LOCATION: SR 715 (PALM BEACH CO.) TEST RITE #4.0 FERFCRMED DATE: 04-30-86 BY: DAVE/KHASI/ED CALIBRATION INFORMATION: DELTA A 0.19 BARS DELTA B 0.36 BARS GAGE 0 0.05 BARS GWT DEPTH 1.55 M ROD DIA. - 3.70 CM FR.RED.DIA. 3.70 CM ROD WT.= 6.50 KG/M DELTA/PHI= 0.50 BLADE T=13.70 MM 1 BAR - 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 Z THRUST A B ED ID Kn uo OAT1A SV PC OCR KO CU FHI M SOIL TYFE (M) (KG) (DAR) (BAR) (BAR) (PAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) A A A A A AAA AAA A A A A A ..... ***** ***** AAAAA A A A A A A ****** ****** AAAAA AAAAA ***** ***** AAAAA AAAAAA ************ 0.91 7000. 9.70 40.00 1084. 3.74 68.46 0.000 2.150 0.122 41.90 AAAAA 7.75 46.0 4684.0 SAND 1.11 7950. 12.40 40.00 986. 2.54 68.13 0.000 2.150 0.164 60.40 AAAAA 7.89 44.8 4254.4 SILTY SAND 1.31 3370. 6.70 70.10 468. 2.18 30.46 0.000 2.000 0.203 17.40 05.51 3.55 42.5 1664.2 SILTY SAND 1.51 1715. 1.00 3.50 71. 1.96 4.40 0.000 1.700 0.237 123.1 SILTY SAND 1.71 1315. 1.20 2.60 31. 0.70 5.08 0.016 1.600 0.253 1.08 4.28 1.17 0.178 56.0 CLAYEY SILT 1.91 1250. 1.00 2.30 27. 0.74 4.04 0.035 1.600 0.264 0.79 2.99 0.99 0.140 43.1 CLAYEY SILT 2.11 1225. 0.80 1.50 5. 0.18 3.20 0.055 1.500 0.274 0.57 2.08 0.83 0.109 7.3 MUD 2.31 1360. o . 1.60 13. 0.49 2.62 0.075 1.600 0.286 0.43 1.57. 0.70 0.088 14.4 SILTY Cl .AY 2.51 1315. 0.70 1.60 13. 0.50 2.45 0.094 1.600 0.298 0.41 1.37 0.66 0.084 13.5 SILTY CLAY 2.71 1315. 0.70 1.40 5. 0.22 2.34 0.114 1.500 0.307 0.39 1.28 0.63 0.082 5.5 MJD 2.91 1500. 0.80 1.50 5. 0.20 2.52 0.133 1.500 0.317 0.45 1.43 0.68 0.093 5.9 MUD 3.11 1515. 1.60 3.40 46. 0.86 4.63 0.153 1.600 0.37.9 1.22 3.71 1.10 0.207 78.5 CLAYEY SILT 3.31 1545. 1.40 3.00 38. 0.84 3.06 0.173 1.600 0.341 0.95 2. 79 0.96 0.170 58.9 CLAYEY SILT 3.51 1595. 1.10 3.70 75. 2.28 2.67 0.192 1.700 0.355 0.03 0.09 0.09 44.8 96.3 SILTY SAND 3.71 1800. 1.50 7.50 199. 4.95 3.12 0.212 1.800 0.370 0.07 0.18 0.13 45.0 295.6 SAND 3.91 5780. 16.80 40.00 825. 1.53 39.75 0.232 2.100 0.392 63.66 ***** 4.81 40.4 3141.3 SANDY SILT 4.11 4160. 6.90 25.60 661. 3.7.4 14.29 0.251 2.000 0.411 7.54 18.31 1.58 43.8 1876.8 SILTY SAND 4.31 1765. 2.10 6.80 151. 2.47 4.12 0.271 1.800 0.427 0.62 1.45 0.43 42.6 257.1 SILTY SAND 4.51 2030. 6.90 22.70 556. 2.67 13.40 0.290 2.000 0.447 9.48 21.21 1.73 38.1 1543.0 SILTY SAND 4.71 1780. 3.20 9.70 217. 2.29 5.88 0.310 1.900 0.464 1.80 3.87 0.73 40.8 436.7 SILTY SAND 4.91 1850. 4,80 13.40 293. 2.01 8.73 0.330 1.900 0.482 4.38 9.08 1.14 39.1 696.0 SILTY SAND 5.11 2575. 2.20 13.20 381. 7.47 2.94 0.349 1.900 0.500 545.7 SAND 5.31 2245. 1.30 9.40 275. 11.43 1.35 0.369 1.800 0.516 233.8 SAND 5.51 2240. 5.10 9.80 151. 0.94 8.74 0.389 1.800 0.531 5.30 9.98 1.69 357.6 SILT 5.71 1870. 2.30 8.40 202. 3.37. 3.21 0.408 1.800 0.547 0.54 0.98 0.36 42.2 305.8 SAND 5.91 7.750. 0.80 4.70 104. 8. 10 0.66 0.428 1.700 0.561 88.3 SAND END OF SOI BID I NO TEST NO. 2 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE,J-GED,MARCH 80) K0 IN SANDS DETERMINED USING SCHMERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: SR 715 (PALM BEACH CO.) TEST SITE #3.0 PERFORMED DATE: 04-30-86 BY: DAVE/KHASI/ED CALIBRATION INFORMATION: DELTA A 0.19 BARS DELTA B 0.36 BARS ROD DIA.= 3.70 CM FR.RED.DIA.= 3.70 CM 1 BAR = 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI z THRUST A B ED ID KD UO GAMMA (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) ***** ****** ***** ***** ***** ***** ***** ****** ****** 0.81 8950. 15.50 40.00 873. 1.74 ***** 0.000 2.100 1.01 9790. 23.20 40.00 592. 0.76 ***** 0.000 2.100 1.21 5257. 8.60 23.70 530. 1.91 39.57 0.000 2.000 GAGE 0 = 0.05 BARS GMT DEFTH= 1.55 M ROD WT.= 6.50 KG/M DELTA/FHI= 0.50 BLADE 1=13.70 PM ANALYSIS USES H20 UNIT WEIGHT 1.000 T/M3 SV PC OCR KO CU PHI M SOIL TYPE (BAR) (BAR) (BAR) (DEG) (BAR) ****** ***** ***** ***** ***** ***** ****** ************ 0.122 ***** ***** 13.97 44.3 4223.3 SANDY SILT 0.163 ***** ***** 7.78 7.142 2951.5 CLAYEY SILT 0.202 26.97 ***** 4.53 44.1 2015.7 SILTY SAND END OF SOUNDING 426 UNIV. OF FLORIDA CIVIL ENG. DEFT.- DR. B.E. RUTH TEST NO. 1 FILE NAME: FAVTMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NIY1BER: 2.45-D51 RECORD OF DILATCMETER TEST NO. 1 USING DATA REDUCTION ROCEDURES IN MARCHETTI (ASCE, J-GED, MARCH 60) KO IN SANDS DETERMINED USING SCHMER1MANN METHOD (1983) FHI ANGI.E CALCU1.ATION BASED ON DURGUNOGT.U AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) FHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXFRESSION (ASCE,J-GED.NOV 76) MODIFIED MAYNE AND KIR.HAWY FCTOtH.A USED FOR OCR IN SANDS (ASCE,.T-OED.JUNE 82) LOCATION: SR 12 (GADSDEN CO.) TEST SITE 1*2.5 FERFOPTED DATE: 08-12-86 BY: DAVE/KUASI/ED CALIBRATION INFOFMATICM: DELTA A 0.22 BARS DELTA B 1. AO BARS GAGE 0 0.05 BARS CWT DEPTH-10.00 M ROD DIA.= 3.70 CM FR.RED.DIA.= 3.70 CM ROD WT.= 6.50 KG/M DELTA/FHI= 0.50 BLADE T=13.70 t-M 1 BAR 1 .019 KO/CM2 - 1.044 TSF - 14.51 PSI z THRUST A B ED ID KD uo GAM-1A ***** (KG) il A (BAR) (BAR) (BAR) ***** A* AAA ***** (BAR) A A A A A A (T/M3) ...... 0.24 1110. *t. 20 21.20 560. 4.48 81.84 0.000 2.000 0.44 3025. 9.BO 35.20 866. 2.84 AAA AA 0.000 2.150 0.64 2635. 10.40 32.00 728. 2.19 74.5A 0.000 2.150 0.84 1560. 5. 50 19.50 451. 2.57 30. 13 0.000 2.000 1.04 1040. 3.70 13.80 309. 2.58 16.81 0.000 1.900 1.24 775. Z.PO 11.40 254. 2.80 10.02 0.000 1.900 1.44 680. 1.60 10.60 269. 5.53 5.05 0.000 1.800 1.64 685. 2.60 10.70 236. 2.78 7.77 0.000 1.900 1.84 735. 2.70 11.30 254. 2.91 7.16 0.000 1.900 2.04 770. 2.80 11.60 262. 2.89 6.70 0.000 1.900 2.24 780. 3.00 11.70 258. 2.64 6.60 0.000 1.900 2.44 805. 3.00 11.90 265. 2.72 6.05 0.000 1.900 2.64 880. ;v 10 12.50 283. 2.84 5.75 0.000 1.900 2.84 965. 3.30 13.30 305. 2.88 5.66 0.000 1.900 3.04 1085. 3.70 14.20 324. 2.72 5.95 0.000 1.900 3.24 1205. 3.70 14.60 338. 2.86 5.55 0.000 1.900 3.44 1410. 4.30 16.30 378. 2.76 6.07 0.000 1.900 3.64 1530. 4.40 16.40 378. 2.69 5.87 0.000 2.000 3.84 1295. 5.60 18.80 422. 2.34 7.12 0.000 2.000 4.04 1410. 5.20 18.20 415. 2.49 6.25 o.oon 2.000 4.24 1790. 7.30 27.60 677. 2.98 8.10 0.000 2.000 4.44 1680. 7.70 22.60 484. 1.94 8.51 0.000 2.000 4.64 1855. 6.30 23.70 575. 2.92 6.41 0.000 2.000 4.84 2240. 7.70 27.30 655. 2.71 7.53 0.000 2.000 5.04 2330. 7.70 26.00 608. 2.49 7.29 0.000 2.000 5.24 2250. 6.80 23.70 557. 2.59 6.18 0.000 2.000 5.44 2310. 7. no 24.50 546. ? 15 7.02 o.oon 2.000 5.64 2646. ft. rn 26 80 604 . 2.1n 7 34 n.nno 2.000 END OF SOUNDING ANALYSIS USES H20 UNIT WEIGHT 1.000 T/M3 sv PC OCR KO CU nu M SOIL TYPE {BAR) (BAR) (BAR) (DEG) (BAR) AAAAAA AAA AA ***** ***** ***** AA AA A ****** ************ 0.044 2516.2 SAND 0.086 80.52 ***** 12.19 40.4 4070.1 SILTY SAND 0.128 76.31 ***** 9.04 37.6 3204.4 SILTY SAND 0.168 16.54 98.63 3.70 37.8 1598.6 SILTY SAND 0.205 6.77 33.04 2.15 36.6 924.4 SILTY SAND 0.242 3.63 14.99 1.47 35.3 654.8 SILTY SAND 0.278 1.00 3.60 0.73 37.1 512.5 SAND 0.315 2.75 8.73 1.15 33.9 537.6 SILTY SAND 0.352 2.66 7.56 1.08 34.1 561.4 SILTY SAND 0.389 2.64 6.79 1.03 34.1 562.4 SILTY SAND 0.427 2.89 6.77 1.03 33.6 549.3 SILTY SAND 0.464 2.72 5.86 0.96 33.7 544.8 SILTY SAND 0.501 2.67 5.32 0.92 34.2 570.6 SILTY SAND 0.539 2. 77 5.14 0.90 34.6 611.3 SILTY SAND 0.576 3.19 5.53 0.93 34.9 659.9 SILTY SAND 0.613 2.94 4.80 0.87 35.8 670.8 SILTY SAND 0.650 3.56 5.47 0.92 36.3 778.7 SILTY SAND 0.690 3.51 5.09 0.88 36.8 766.6 SILTY SAND 0.729 5.78 7.93 1.11 33.7 924.2 SILTY SAND 0.768 4.71 6.13 0.98 34.9 860.8 SILTY SAND 0.807 7.65 9.47 1.20 35.3 1568.4 SILTY SAND 0.847 9.18 10.84 1.28 33.9 1136.4 SILTY SAND 0.886 5.45 6.15 0.97 36.2 1214.0 SILTY SAND 0.925 7.39 7.98 1.10 36.8 1473.1 SILTY SAND 0.965 7.23 7.50 1.06 37.0 1346.5 SILTY SAND 1.004 5.62 5.60 0.93 37,2 1152.1 SILTY SAND 1.043 7.48 7.17 1.05 36.5 1186.0 SILTY SAND 1.082 8.28 7.65 1.08 36.9 1337.9 SILTY SAND 427 UNIV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 2 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D5I RECORD OF DILATCMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE.J-GED,MARCH 80) K0 IN SANDS DETERMINED USING SCHMERIMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.72 BARS USING BALIGHS EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED,JUNE 82) LOCATION: SR 12 (GADSDEN CO.) TEST SITE #3.5 PERFORMED DATE: 08-12-86 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A = 0.22 BARS DELTA B 1.40 BARS GAGE 0 = 0.05 BARS GWT DEPTH=10.00 M ROD DIA. 3.70 CM FR.RED.DIA.= 3.70 CM ROD WT.= 6.50 KG/M DELTA/PHI= 0.50 BLADE T=13.70 Ml 1 BAR 1.019 KG/CM2 = 1.044 TSF = 14.51 PSI z THRUST A B ED ID KD UO gapma (M) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) ***** ****** ***** ***** ***** ***** ***** ****** ****** 0.24 1640. 4.80 20.40 509. 3.44 97.07 0.000 2.000 0.44 3170. 12.80 29.10 535. 1.26 ***** 0.000 2.100 0.64 2590. 9.60 29.10 651. 2.12 69.66 0.000 2.150 0.84 1550. 5.50 19.30 444. 2.53 30.37 0.000 2.000 1.04 1005. 3.60 13.70 309. 2.66 16.41 0.000 1.900 1.24 765. 3.10 11.60 251. 2.47 12.13 0.000 1.900 1.44 645. 2.60 9.80 203. 2.35 8.94 0.000 1.900 1.64 655. 2.70 10.70 232. 2.63 8.08 0.000 1.900 1.84 715. 2.70 10.60 229. 2.58 7.24 0.000 1.900 2.04 830. 2.80 11.40 254. 2.80 6.71 0.000 1.900 2.24 865. 2.90 12.10 276. 2.96 6.29 0.000 1.900 2.44 850. 2.90 11.90 269. 2.87 5.81 0.000 1.900 2.64 910. 3.10 12.40 280. 2.79 5.75 0.000 1.900 2.84 995. 3.20 13.20 305. 2.98 5.47 0.000 1.900 3.04 1125. 3.40 13.50 309. 2.83 5.45 0.000 1.900 3.24 1315. 3.80 15.00 349. 2.88 5.68 0.000 1.900 3.44 1575. 4.60 16.60 378. 2.56 6.51 0.000 2.000 3.64 1750. 4.90 18.30 429. 2.76 6.47 0.000 2.000 3.84 1485. 7.00 22.00 488. 2.16 8.88 0.000 2.000 4.04 1375. 4.90 17.10 385. 2.45 5.89 0.000 2.000 4.24 1875. 7.60 24.40 553. 2.27 8.65 0.000 2.000 4.44 2050. 7.30 27.20 666. 2.93 7.72 0.000 2.000 4.64 1960. 7.20 25.20 597. 2.63 7.37 0.000 2.000 4.84 2295. 7.30 24.80 579. 2.50 7.19 0.000 2.000 5.04 2295. 8.00 26.50 615. 2.42 7.57 0.000 2.000 5.24 2500. 9.20 30.80 728. 2.51 8.29 0.000 2.150 5.44 2595. 7.50 26.70 641. 2.72 6.47 0.000 2.000 5.64 3210. 7.40 27.10 659. 2.85 6.13 0.000 2.000 END OF SOUNDING ANALYSIS USES H20 UNIT WEIGHT = 1.000 T/M3 SV PC OCR KO CU PHI M SOIL TYPE (BAR) (BAR) (BAR) (DEG) (BAR) ****** ***** ***** ***** ***** ***** ****** ************ 0.044 2369.5 SAND 0.085 ***** ***** 17.33 37.3 2686.4 SANDY SILT 0.127 64.55 ***** 8.43 38.1 2825.8 SILTY SAND 0.167 16.74 ***** 3.73 37.7 1576.1 SILTY SAND 0.204 6.45 31.61 2.10 36.5 917.2 SILTY SAND 0.241 4.61 19.10 1.65 34.4 672.5 SILTY SAND 0.279 3.15 11.29 1.30 33.4 487.6 SILTY SAND 0.316 3.02 9.57 1.20 33.1 536.8 SILTY SAND 0.353 2.75 7.80 1.09 33.8 505.8 SILTY SAND 0.390 2.59 6.64 1.01 34.9 546.4 SILTY SAND 0.428 2.56 5.98 0.96 34.9 578.9 SILTY SAND 0.465 2.48 5.34 0.92 34.4 544.1 SILTY SAND 0.502 2.64 5.26 0.91 34.5 562.8 SILTY SAND 0.540 2.58 4.77 0.87 35.0 603.0 SILTY SAND 0.577 2.68 4.65 0.85 35.7 607.6 SILTY SAND 0.614 2.98 4.85 0.86 36.5 699.8 SILTY SAND 0.653 3.92 6.00 0.95 37.0 799.6 SILTY SAND 0.693 4.04 5.83 0.94 37.5 907.7 SILTY SAND 0.732 8.58 11.72 1.32 33.6 1165.4 SILTY SAND 0.771 4.28 5.54 0.94 34.9 779.0 SILTY SAND 0.810 8.63 10.65 1.26 35.3 1309.3 SILTY SAND 0.850 7.11 8.37 1.12 36.5 1514.2 SILTY SAND 0.889 7.01 7.89 1.10 36.0 1329.3 SILTY SAND 0.928 6.72 7.24 1.04 37.2 1274.6 SILTY SAND 0.967 7.85 8.12 1.11 36.7 1382.5 SILTY SAND 1.010 9.67 9.57 1.20 36.6 1697.0 SILTY SAND 1.049 6.19 5.90 0.94 38.0 1354.3 SILTY SAND 1.088 5.34 4.91 0.85 39.8 1363.3 SILTY SAND 428 UJIXV. OF FLORIDA CIVIL ENG. DEPT.- DR. B.E. RUTH TEST NO. 3 FILE NAME: PAVEWENT-SUBGRADE MATERIALS CHARACTERIZATICN FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 3 USING DATA REDUCTION PROCEDURES IN MARCHEITI (ASCE.J-(JED,MARCH dO) KO IN SANDS DETERMINED USING SCIMERTMANN METHCO (1983) EHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE,RALEIGH CONF.JUNE 75) FHI ANGLE NORMALIZED TO Z.72 BARS USING BALIGH'S EXPRESSION (ASCE,J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE.J-GED. JUNE 32) LOCATION: SR 12 (GADSDEN CO.) TEST SITE #4. 5 PERFORMED DATE: 08-12-36 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A 0.22 BARS DELTA B 1.AO BARS ROD DIA.- 3.70 CM FR.RED.DIA.- 3.70 CM 1 BAR - 1.019 KG/CM2 - 1.044 TSF - 14.51 . FSI z THRUST A B ED ID KD uo GAf-MA CM) r**** (KG) ****** (BAR) ***** (BAR) ***** (BAR) ***** ***** ***** (BAR) ****** (T/M3) ****** 0.24 1950. 4.10 13.50 466. 3.70 82.52 0.000 2.000 0.44 3225. 11.90 34.20 753. 1.97 0.000 2. 150 0.64 2510. 9.40 28.70 644 . 2. 14 67.65 0.000 2. 150 0.34 1640. 6.30 20.50 458. 2.26 34.84 0.000 2.000 1.04 1030. 4.30 15.10 334. 2.40 19.57 0.000 1.900 1.24 305. 3.10 11.90 262. 2.59 12.02 0.000 1.900 1.44 640. 2.50 10.10 213. 2.65 8.48 0.000 1.900 1.64 640. 2.50 9.80 207. 2.50 7.53 0.000 1.900 1.34 725. 3.00 11.20 240. 2.43 8.02 Q.OOQ 1.900 2.04 795. 3.00 11.30 243. 2.47 7.25 0.000 1.900 2.24 345. 3.00 11.70 258. 2.64 6.57 0.000 1.900 2.44 aso. 3.10 12.30 276. 2.75 6.20 0.000 1.900 2.64 995. 3.20 12.80 291. 2.32 5.90 0.000 1.900 2.84 1080. 3.70 14.10 320. 2.69 6.35 0.000 1.900 3.04 1115. 3.30 13.90 327. 3.12 5.23 0.000 1.900 3.24 1325. 4.00 15.20 349. 2.73 6.00 0.000 1.900 3.44 1510. 4.70 17.20 396. 2.64 6.61 0.000 2.000 3.64 1200. 3.00 14.40 324. 2.57 5.24 0.000 1.900 3.34 970. 3.90 13.30 302. 2.33 5.02 0.000 1.300 4.04 1030. 4.00 14.00 305. 2.35 4.90 0.000 1.900 4.24 1165. 5.00 16.50 360. 2.22 5.80 0.000 2.000 4,44 1625. 6.30 24.20 593. 3.02 6.70 0,000 2.000 4.64 2205. 6.70 23.80 564. 2.67 6.90 0.000 2.000 4.34 2345. 6.90 25.00 600. 2.77 6.76 0.000 2.000 5.04 2705. 7.60 27.30 659. 2.76 7.13 0.000 2.000 5.24 3130. 10.80 35.20 a3o. 2.43 9.78 0.000 2.150 5.44 2945. 9.20 30.10 702. 2.41 8.03 0.000 2.150 5.64 2565. 8.00 25.60 582. 2.28 6.79 0.000 2.000 GAGE 0 - 0.05 BARS GWT DEFTH-10. ,00 M RCO WT. 6.50 KG/M DELTA/PHI- 0. .50 BLADE T-13.70 PM analysis uses H20 UNIT WEIGHT - 1.000 T/M3 sv rc OCR KO cu PHI M SOIL ' TYPE (BAR) (BAR) (BAR) (DEG) (BAR) ****** ***** ***** ***** ***** ***** ****** ***********1 0.044 2094.5 BAND 0.066 15.41 J8.7 3702.5 SILTY SAND 0. 126 61.70 8.20 Jd.o 2776.4 SILTY SAND 0.168 22.64 4.29 37.1 1637.5 SILTY SAND 0.205 9.32 45.46 2.50 35.9 1043.8 SILTY SAND 0.242 4.47 18.45 1.62 35.0 699.5 SILTY SAND 0.230 2.35 10.20 1.24 33.7 512.7 SILTY SAND 0.317 2.67 8.42 1.13 33.3 464.5 SILTY SAND 0.354 3.36 9.49 1.20 33.2 551.5 SILTY SAND 0.391 3.06 7.81 1.09 34.0 537.7 SILTY SAND 0.429 2.61 6.54 1.01 34.4 548.2 SILTY SAND 0.466 2.77 5.94 0.96 34.5 573.a SILTY SAND 0.503 2.70 5.36 0.91 35.2 592.0 SILTY SAND 0.541 3.31 6.12 0.97 35.1 670.5 SILTY SAND 0.578 2.50 4.32 0.82 35.6 633.6 SILTY SAND 0.615 3.30 5.36 0.91 36.3 714.6 SILTY SAND 0.654 4.11 6.28 0.98 36.5 844.7 SILTY SAND 0.692 3.13 4.53 0.85 35.1 621.5 SILTY SAND 0.729 3. J5 4.60 0.88 32.7 564.9 SILTY SAND . 766 J.J1 4.32 0.85 33.5 564.6 SILTY SAND 0.806 4.67 5.30 0.97 32.9 719.9 SILTY SAND 0.845 5.30 6.37 1.03 35.1 1276.2 SILTY SAND 0.884 5.37 6.64 1.00 37.5 1223.4 SILTY SAND 0.923 5.37 6.36 0.98 37.8 1293.8 SILIY SAND 0.963 6.54 6.79 1.00 38.5 1450.2 SILTY SAND 1.005 12.48 12.42 1.34 37.3 2058.6 SILTY SAND 1.047 9.01 8.60 1.13 38.0 1616.3 san SAND 1.086 7.14 6.57 1.00 37.4 1248.3 SILTY SAND END OF SOUNDING 429 UNIV. OF FLORIDA CIVIL ENG. DEPT. DR. B.E. RUTH TEST NO. 1 FILE NAME: PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATOMETER TEST NO. 1 USING DATA REDUCTION PROCEDURES IN MARCHETTI (ASCE.J-GED.MARCH SO) KQ IN SANDS DETERMINED USING SCUMERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE.RALEIGH CONF.JUNE 75) PHI ANGLE NORMALIZED TO 2.7Z BARS USING BALIGHS EXPRESSION (ASCE.J-GED,NOV 76) MODIFIED MAINE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE.J-GED,JUNE 62) LOCATION: SR ISC (MARTIN CO.) TEST SITE itt.5 PERFORMED DATE: 09-30-86 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A 0.22 BARS DELTA B 1.30 BARS GAGE 0 0.05 BARS GWT DEPTH- 1.67 M ROD DIA.- 3.70 CM FR.RED.DIA.- 3.70 CM ROD WT.- 6.50 KG/M DELIA/PHI- 0.50 BLADE T-13.70 IM 1 BAR 1.019 KG/CM2 1.04* TSF 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT 1.000 T/M3 z (M) THRUST (KG) A (BAR) B (BAR) ED (BAR) ID KD UO (BAR) GArtlA (T/M3) sv (BAR) PC (BAR) OCR KO CU (BAR) PHI (DEC) M (BAR) SOIL TYPE 0.39 2790. 0.50 16.20 492. 21.16 0.84 0.000 1.800 0.800 418.2 SARD F01 - -0.04 PO - 0.67 pi - 14.85 0.59 1985. 5.00 13.40 251. 1.50 5.78 0.000 1.800 0.835 3.36 4.74 0.84 38.1 493.3 SARD* SILT 0.79 880. 2.60 8.00 141. 1.58 2.36 0.000 1.300 0.871 1.33 2.22 0.64 32.6 133.0 SANDY SILT 0.99 2330. 3.30 18.30 513. 5.34 3.05 0.000 1.900 0.908 0.87 0.36 0.35 42.6 752. J SAND 1.19 3605. 6.50 25.10 622. 3.08 6.14 0.000 2.000 0.94 7 4.00 4.22 0.76 41.3 1232.1 SILTV SAND 1.39 3195. 6.40 30.40 819. 4.33 5.52 0.000 2.000 0.986 3.68 3.73 0.73 40.9 1625.0 SAND 1.59 1675. 7.60 23.30 517. 2.11 s.as 0.000 2.000 1.026 7.37 7.67 1.10 33.5 1112.3 SILTY SAND 1.79 640. 1.30 4.20 50. 1.03 1.33 0.000 1.600 1.057 0.56 0.53 0.34 42. 7 SILT 1.99 380. 1.00 3.10 21. 0.54 1.05 0.012 1.600 1.077 0.39 0.37 0.25 0.106 18.0 SILTT CLAV 2.19 335. 1.00 2.90 14. 0.36 1.03 0.031 1.600 1.089 Q .39 0.35 a. 24 0.104 11.3 SILTY CLAY 2.39 290. 0.90 2.70 10. 0.29 0.91 0,051 1.500 1.098 0.32 0.30 0.19 0,091 3; 7 MUD 2.59 315. 0.90 2.70 10. 0.30 0.89 0,071 1.500 1.108 0.31 0.28 0.18 0.039 3. 7 MUD 2.79 400, 1.00 3.00 17. 0.48 0.94 0.090 1.600 1.120 0.35 0.31 0.20 0.096 14 3 SILTY CLAV 2.99 400. 1.20 3.00 10. 0.24 1.10 0. 110 1.500 1.130 0.45 0.40 0.27 0.118 d. 7 MUD 3.19 44Q. 1.00 2.60 3. 0.08 0.91 0.130 1.500 1.140 0.33 0.29 0.13 0.094 2.5 MUD 3.39 515. 0.80 2.40 3. 0. 10 0.71 0.149 1.500 1.149 0.23 0.20 0. 10 0.089 2. 5 MUD 3.59 575. 1.10 2.70 3. o.oa 0.95 0.169 1.500 1.159 0.36 0. J1 0.21 0.100 2.5 MUD 3.79 720. 1.00 2.70 7. 0.19 0.83 0.188 1.500 1.169 0.30 0.25 0.16 0.086 55 MUD 3.99 735. 1.00 2.70 7. 0.20 0.31 0.208 1.500 1. 179 0.29 0.24 0.15 0.084 5.6 MUD 4.19 685. o.ao 2.IQ -1. -0.04 0.228 poi - 0.77 PO - 0 7 7 PI - o. ;s cuestionable 4.39 1040. 0.40 1.30 -1. -0.06 0.247 POI - 0.57 PO - 0.57 PI - 0 55 CUESTIONABLE 4.59 1885. 2.10 9.90 229. 3.30 1.39 0.267 1.300 1.217 0.73 0.60 0.31 38.d iJ* 5 SAND 4.79 3025. 2.30 17.30 491. 9.3a 1.22 0.287 1.900 1.235 0.22 0. 18 0.15 42.6 -17 5 SAND 4.99 5195. 4.20 34.60 1052. 11.57 2.09 0.306 2.000 1.254 0.02 0.02 0.04 46.2 1133.2 SAND END OF SOUNDING 430 UNIV. OF FLORIDA CIVIL ENG. DEPT. DR. B.E. RUTH TEST NO. 2 FILE NAME; PAVEMENT-SUBGRADE MATERIALS CHARACTERIZATION FILE NUMBER: 245-D51 RECORD OF DILATCMETER TEST NO. 2 USING DATA REDUCTION PROCEDURES IN MARCUETTI (ASCE,J-GED,MARCH 30) K0 IN SANDS DETERMINED USING SCHMERTMANN METHOD (1983) PHI ANGLE CALCULATION BASED ON DURGUNOGLU AND MITCHELL (ASCE.RALEIGH CQNF,JUNE 75) PHI ANGLE NORMALIZED 10 2.72 BARS USING BALIGH'S EXPRESSION (ASCE.J-GED,NOV 76) MODIFIED MAYNE AND KULHAWY FORMULA USED FOR OCR IN SANDS (ASCE,J-GED.JUNE 82) LOCATION: SR 15C (MARTIN CO.) TEST SITE 42.5 PERFORMED DATE: 09-30-86 BY: DAVE/KWASI/ED CALIBRATION INFORMATION: DELTA A -0.22 BARS DELTA B 1.30 BARS GAGE 0 *0.05 BARS GWT DEPTH- 1.87 M ROD DIA. 3.70 CM FR.RED .DIA. - 3.70 CM ROD WT 6.50 KG/M DELTA/PHI- 0.50 BLADE 1-13.70 iti 1 BAR - 1.019 KG/CM2 - 1.044 TSF - 14.51 PSI ANALYSIS USES H20 UNIT WEIGHT - 1.000 I/M3 Z THRUST A B ED ID KD UO GAMiA SV PC OCR KO CU PHI M SOIL IYPE CM) (KG) (BAR) (BAR) (BAR) (BAR) (T/M3) (BAR) (BAR) (BAR) (DEG) (BAR) 0.39 3090. 3.20 25.00 739. 9.04 2.94 0.000 1.900 0.800 0.17 0.21 0.15 45.6 1062.7 SAND 0.59 2140. 2.20 9.00 192. 2.63 2.52 0.000 1.900 0.337 0.67 0.80 0.33 41.6 244.0 SILTY SAND 0.79 475. 1.40 3.40 17. 0.33 1.78 0.000 1.600 0.869 0.72 0.33 0.43 0.165 14.3 CLAY 0.99 2490. 1.20 16.00 484. 19.75 0.78 0.000 l.aoo 0.904 411.3 SAND 1.19 3495. 6.10 24.40 611. 3.24 5.76 0.000 2.000 0.943 3.51 3.72 0.72 41.6 1235.3 silty Sand 1.39 2835. 6.00 24.40 615. 3.33 5.42 0.000 2.000 0.983 3.76 3.35 0. 75 40.0 1210.4 SAND 1.59 1590. 6.10 16.50 324. 1.60 5.71 0.000 1.950 1.021 5.62 5. 51 0.35 34.1 634.7 SANDY SILI 1.79 765. 2.30 8.00 134. 1.39 2.64 0.000 1.800 1.056 2.31 2. 19 0.67 30.0 161.2 SANDY SILT 1.99 530. 1.00 3.00 17. 0.44 1.05 0.012 1.600 1.076 0.40 0.37 0.25 0.106 14.9 SILTY CLAY 2.19 425. 1.10 2.30 10. 0.24 1.13 0.031 1.500 1.086 0.44 0.41 0.27 0.117 3.7 MUD 2.39 405. 1.00 2.70 7. 0.17 1.01 0.051 1.500 1.095 0.38 0.35 0.23 0.103 5.6 MUD 2.59 425. 1.00 2.70 7. 0.17 0.99 0.071 1.500 1.105 0.37 0.33 0.22 0.101 5.6 MUD 2.79 430. 0.90 2.70 10. 0.30 0.87 0.090 1.500 1.115 0.30 0.27 0.17 0.086 8.7 MUD 2.99 425. 1.00 2.70 7. 0.18 0.93 0.110 1.500 1.125 0.34 0.31 0.20 0.096 5.6 MUD 3.19 485. 0.90 2.60 7. 0.20 0.82 0.130 1.500 1.135 0.28 0.25 0.15 0.082 5.6 MUD 3.39 525. 0.90 2.60 7. 0.21 0.60 0.149 1.500 1.144 0.27 0.24 0.14 0.080 5.5 MUD 3.29 600. 1.20 3.00 10. 0.25 1.03 0.169 1.500 1.154 0.41 0.35 0.24 o.m 3.7 MUD 3.79 765. 1.20 3.00 10. 0.25 1.00 0.188 1.500 1.164 0.40 0.34 0.23 0.103 3.7 MUD 3.39 865. 1.00 2.60 3. 0.09 0.82 0.208 1.500 1.174 0.29 0.25 0.15 0.084 2.5 MUD 4.19 810. 0.90 2.30 -4. -0,14 0.228 POl - 1.08 PO - 1.07 PI - 0.95 QUESTIONABLE 4.39 1090. 0.90 3.00 21. 0.77 0.66 0.247 1.600 1. 195 0.21 0. 18 0.08 0.066 18.0 CLAYEY SILT 4.59 1680. 0.90 3.30 32. 1.22 0.63 0.267 1.600 1.207 0.35 0.29 Q 22 38 6 27.3 SANDY SILT 4.79 2105. 1.30 9.60 225. 4.40 1.21 0.287 1,800 1.223 0.53 0.4J 0.26 39.6 131.4 SAND 4.35 5190. 3.00 14.40 360. 4.37 1.92 0.302 1.900 1.237 J83.6 SAND END OF SOUNDING APPENDIX E RECOVERED ASPHALT RHEOLOGY TEST RESULTS Table E.l Rheology and Penetration of Asphalt Recovered From SR 26 (Gilchrist County) Layer 2: Type I Mix Thickness = 1.75" Temperature F (C) Absolute Viscosity nx(Pa-s) Comp!ex Flow (C) Constant Power Viscosity "loo 275 (135) 8.61 El --- 140 (60) 1.069 E3 1.07 E3 77 (25)(a) 1.32 E6 0.92 1.96 E6 60 (15.6) 1.69 E6 0.74 7.24 E6 41 ( 5) 1.98 E7 0.60 4.18 E8 23 (-5) 1.99 E7 0.54 7.62 E8 (a) Penetration at 77F (25C) = 28 Layer 4: Binder Thickness = 0.5" Temperature F (C) Absolute Viscosity nx(Pa-s) Complex Flow (C) Constant Power Viscosity "ioo(Pa-s) 275 (135) 140 (60) 1.069 E3 1.07 E3 77 (25)(a) 4.75 E5 0.92 6.76 E5 60 (15.6) 1.37 E6 0.73 6.06 E6 41 ( 5) 2.01 E7 0.69 1.89 E8 23 (-5) 5.82 E7 0.67 8.02 E8 (a) Penetration at 77F (25C) = 42 437 Table E.4 Rheology and Penetration of Asphalt Recovered From US 441 (Columbia County) Surface Type I Mix Thickness = 1/2" Temperature F (C) Absolute Viscosity nJPa-s) Complex Flow (C) Constant Power Viscosity nioo(pa-s> 275 (135) 1.383 E3 140 (60) 3.63 E5 3.63 E5 77 (25)(a> 7.95 E5 0.60 7.50 E6 60 (15.6) 3.55 E6 0.89 6.52 E6 41 ( 5) 1.71 E7 0.48 1.15 E9 23 (-5) 2.95 E7 0.57 9.28 E8 (a) Penetration at 77F (25C) = 11 Layer 1: Type I Mix Thickness = 1.0" Temperature F (C) Absolute Viscosity n x(Pa-s) Complex Flow (C) Constant Power Viscosity "ioo 275 (135) 7.62 E2 140 (60) 1.27 E5 1.27 E5 77 (25)(a) 8.98 E5 0.51 1.72 E7 60 (15.6) 2.05 E6 0.82 5.47 E6 41 ( 5) 1.95 E7 0.51 1.02 E9 23 (-5) 1.32 E8 0.77 8.24 E8 (a) Penetration at 77F (25C) = 13 438 Layer 2: Binder Table E.4--continued Thickness = 1.5" Temperature Absolute Complex Constant Power F (C) Viscosity nx(Pa-s) Flow (C) Viscosity "ioo(Pa-s) 275 (135) 1.0119 E3 140 (60) 1.64 E5 1.64 E5 77 (25)(a) 4.62 E5 0.71 1.93 E6 60 (15.6) 8.96 E6 0.50 1.86 E7 41 ( 5) 1.22 E7 0.64 1.60 E8 23 (-5) 5.44 E6 0.41 5.21 E8 (a) Penetration at 77F (25C) = 11 439 Table E.5 Rheology and Penetration of Asphalt Recovered From I-10A (Madison County) Layer 1: Thickness = Temperature F (C) Absolute Viscosity n1(Pa-s) Complex Flow (C) Constant Power Viscosity nioo(Pa-5) 275 (135) 5.68 El 140 (60) 3.81 E2 3.81 E2 77 (25)(a) 2.86 E5 0.98 3.10 E5 60 (15.6) 1.29 E6 0.88 2.36 E6 41 ( 5) 1.30 E7 0.68 1.23 E8 23 (-5) 1.03 E8 0.79 5.23 E8 (a) Penetration at 77F (25C) = 59 Layer 2: Thickness = Temperature Absolute Complex Constant Power F (C) Viscosity Oj(Pa-s) Flow (C) Viscosity nioo(Pa-s) 275 (135) 5.89 El 140 (60) 4.648 E2 4.648 E2 77 (25) 275 (135) 8.90 El 140 (60) 1.55 E3 1.55 E3 77 (25)(a) 6.63 E5 0.72 2.78 E6 60 (15.6) 8.13 E5 0.39 4.27 E7 41 ( 5) 9.396 E6 0.52 3.49 E8 23 (-5) 1.77 E8 0.86 5.22 E8 (a) Penetration at 77F (25C) = 31 442 Table E.6 Rheology and Penetration of Asphalt Recovered From I-10B (Madison County) Layer 1: Thickness = Temperature F (C) Absolute Viscosity n1(Pa-s) Complex Flow (C) Constant Power Viscosity nioo(Pa's> 275 (135) 7.11 El 140 (60) 7.863 E2 7.863 E2 77 (25)(a) 4.78 E5 0.73 1.79 E6 60 (15.6) 1.787 E6 0.78 6.00 E6 41 ( 5) 1.79 E7 0.67 1.95 E8 23 (-5) 1.08 E8 0.77 6.57 E8 (a) Penetration at Layer 2: 77F (25C) = 40 Thickness = Temperature Absolute Comp!ex Constant Power F (C) Viscosity nj(Pa-s) Flow (C) Viscosity nioo 275 (135) 1.529 E2 140 (60) 3.554 E3 3.554 E3 77 (25)(a) 9.70 E5 0.84 2.16 E6 60 (15.6) 2.09 E6 0.67 1.49 E7 41 ( 5) 4.53 E7 0.73 3.46 E8 23 (-5) 7.31 E7 0.75 5.03 E8 (a) Penetration at 77F (25C) = 25 445 Layer 3: Table E.7--continued Thickness = Temperature Absolute Complex Constant Power F (C) Viscosity nJPa-s) Flow (C) Viscosity "ioo 275 (135) 1.882 E2 --- 140 (60) 1.216 E4 1.216 E4 77 (25)(a) 1.257 E6 0.67 8.115 E6 60 (15.6) 2.466 E6 0.81 7.131 E6 41 ( 5) 1.470 E7 0.52 6.297 E8 23 (-5) 1.676 E8 0.78 9.853 E8 (a) Penetration at 77F (25C) = 15 Layer 2: Shell Mix Thickness = 1.5" Temperature F (C) Absolute Viscosity nx(Pa-s) Complex Flow (C) Constant Power Viscosity "looC3-5* 275 (135) 9.302 E2 140 (60) 2.900 E5 2.900 E5 77 (25)(a) 2.166 E6 0.77 8.078 E6 60 (15.6) 2.558 E6 0.74 1.166 E7 41 ( 5) 8.084 E7 0.73 6.755 E8 23 (-5) 3.326 E8 0.87 9.449 E8 (a) Penetration at 77F (25C) = 6 447 Table E.8--continued Layer 3: Type II Mix Thickness = 1.0" Temperature F (C) Absolute Viscosity n^Pa-s) Comp!ex Flow (C) Constant Power Viscosity nioo(Pa-s) 275 (135) 1.846 E2 140 (60) 9.746 E3 9.746 E3 77 (25)(a) 7.810 E5 0.63 5.974 E6 60 (15.6) 1.775 E6 0.67 1.227 E7 41 ( 5) 2.111 E7 0.56 6.702 E8 23 (-5) 1.185 E8 0.72 1.155 E9 (a) Penetration at 77F (25C) = 17 Layer 4: Type I Mix Thickness = 1.5" Temperature F (C) Absolute Viscosity nj(Pa-s) Complex Flow (C) Constant Power Viscosity n100(Pa-s) 275 (135) 2.264 E2 140 (60) 8.493 E3 8.493 E3 77 (25)(a) 8.019 E5 0.60 7.588 E6 60 (15.6) 1.541 E6 0.63 1.376 E7 41 ( 5) 1.833 E6 0.57 2.697 E8 23 (-5) 1.213 E8 0.73 1.079 E9 (a) Penetration at 77F (25C) = 17 Table E.8--continued Layer 5: Shell Mix Thickness = 2.0" Temperature F (C) Absolute Viscosity nj(Pa-s) Complex Flow (C) Constant Power Viscosity nioo(Pa-s) 275 (135) 1.680 E3 140 (60) 4.300 E5 4.300 E5 77 (25)(a) 2.582 E6 0.78 9.263 E6 60 (15.6) 3.521 E6 0.82 9.914 E6 41 ( 5) 1.277 E8 0.76 8.688 E8 23 (-5) (a) Penetration at 77F (25C) = 3 449 Table E.9 Rheology and Penetration of Asphalt Recovered From SR 15A (Martin County) Layer 2: Shell Mix Thickness = 1.0" Temperature F (C) Absolute Viscosity n x(Pa-s) Complex Flow (C) Constant Power Viscosity ni0(Pa-s) 275 (135) 1.231 E2 140 (60) 3.017 E3 3.017 E3 77 (25)(a) 6.950 E5 0.71 3.116 E6 60 (15.6) 1.587 E6 0.77 5.577 E6 41 ( 5) 9.739 E6 0.54 3.010 E8 23 (-5) 6.567 E7 0.66 1.021 E9 (a) Penetration at 77F (25C) = 26 Layer 3: Type II Mix Thickness = 1.0" Temperature F (C) Absolute Viscosity n^Pa-s) Complex Flow (C) Constant Power Viscosity n100(Pa-S) 275 (135) 1.289 E2 140 (60) 4.213 E3 4.213 E3 77 (25)(a) 7.858 E5 0.62 6.442 E6 60 (15.6) 1.332 E6 0.60 1.431 E7 41 ( 5) 9.00 E6 0.56 2.247 E8 23 (-5) 1.181 E8 0.76 7.949 E8 (a) Penetration at 77F (25C) = 23 450 Table E.9--continued Layer 4: Type I Mix Thickness = 1.75" Temperature F (C) Absolute Viscosity nJPa-s) Complex Flow (C) Constant Power Viscosity nioo 275 (135) 1.215 E2 140 (60) 4.823 E3 4.823 E3 77 (25)(a) 8.670 E5 0.60 8.373 E6 60 (15.6) 1.353 E6 0.64 1.092 E7 41 ( 5) 9.240 E6 0.55 2.554 E8 23 (-5) 9.889 E7 0.77 5.945 E8 (a) Penetration at 77F (25C) = 21 Layer 5: Shell Mix Thickness = 3.5" Temperature F (C) Absolute Viscosity n1(Pa-s) Complex Flow (C) Constant Power Viscosity "ioo(Pa-s) 275 (135) 2.903 E2 140 (60) 1.500 E5 1.500 E5 77 (25)(a) 1.695 E6 0.73 7.751 E6 60 (15.6) 1.612 E6 0.69 9.534 E6 41 ( 5) 5.599 E7 0.73 4.418 E7 23 (-5) 1.554 E8 0.77 9.905 E8 (a) Penetration at 77F (25C) = 9 451 Table E.10 Rheology and Penetration of Asphalt Recovered From SR 715 (Palm Beach County) Layer 1: Type I Mix Thickness = 2.0" Temperature F (C) Absolute Viscosity nx(Pa-s) Comp!ex Flow (C) Constant Power Viscosity nuo(Pa-s) 275 (135) 2.083 E2 140 (60) 1.072 E4 1.072 E4 77 (25) 4.411 E5 0.70 1.940 E6 60 (15.6) 1.477 E6 0.67 9.844 E6 41 ( 5) 7.187 E6 0.56 1.684 E8 23 (-5) 4.220 E7 0.64 7.247 E8 (a) Penetration at 77F (25C) = 33 Layer 4: Shell Mix Thickness = 2" Temperature F (C) Absolute Viscosity n1(Pa-s) Comp!ex Flow (C) Constant Power Viscosity ni00(Pa-s) 275 (135) 9.17 El 140 (60) 5.413 E3 5.413 E3 77 (25)(a) 1.013 E6 0.62 8.814 E6 60 (15.6) 1.499 E6 0.61 1.539 E7 41 ( 5) 1.666 E7 0.58 4.071 E8 23 (-5) 6.483 E7 0.66 1.005 E9 (a) Penetration at 77F (25C) = 20 454 Layer 5: Binder Table E.ll--continued Thickness = 1/2" Temperature Absolute Complex Constant Power F (C) Viscosity nj(Pa-s) Flow (C) Viscosity n 10 0 t (E )1/3 [ 1 2 12 1 1 Eqn. F.4 10. Compare E2 from steps 8 and 9; use an average, if possible. 11. If Ex is unknown, use an average value of E calculated from Equa tions F.l and F.2, if possible, and t + t2 as composite layer thickness. 12. Calculate E3 using Equation F.5. E3 = 8.7451(D3 D4)1*0919 Eqn. F.5 13.Calculate E4 from Equation F.6. E4 = 5.40(D5)"1- Eqn. F.6 Note that in Equations F.l through F.6 modulus E.¡ is in ksi, deflection D.¡ is in mils, and thickness, t3- in inches. 14.Use Ej, E2, or E ; Eg and E4 in an elastic layer computer program to calculate Dynaflect deflections, Dx through Dg with coordinates corresponding to that of Figure F.l. Reasonable values of 461 15. Poisson's ratio can be assumed without much error on the predicted deflections. The following range of Poisson's ratio are suggested for use in elastic layer analysis: Material u Asphalt Concrete 0.30 0.40 Limerock Base 0.30 0.40 Sand-Clay Base 0.35 0.40 Stabilized Subgrade 0.35 0.40 Subgrade 0.35 0.45 Compare measured with predicted deflections; adjust layer moduli to match measured deflections, as required. APPENDIX G PARTIAL LISTING OF DELMAPS1 COMPUTER PROGRAM o o n c * C PROGRAM DELMAPS1 * ^ A ******* rtiSrVttfrVfrttfrft * C PROGRAM DELMAPS1 * C * C DYNAFLECT EVALUATION OF LAYER MODULI IN ASPHALT PAVEMENT SYSTEMS * C * C VERSION 1 * C * £ ************************** A ********************************* ******* * * C C THIS PROGRAM IS A MODIFICATION TO BISAR PROGRAM TO C CALCULATE LAYER MODULUS VALUES FROM DEFLECTIONS C MEASURED WITH THE MODIFIED DYNAFLECT TESTING SYSTEM C c EX C ARRAYS- DIMENSIONS AND DATA STATEMENTS C LOGICAL STRESS,EPS,RLOW,AID(27),N,L,N2,L2,NZEP,NZEQ BI INTEGER REQEST(27),IQ(3),DATE(3),ISTRSS(27),INTV(10),IVERI(7), BI &IVER2(10) BI REAL NU,K5,MU,LDSTRS(10),HOSTR(10),LOAD,INT(17),V(15),X(10),Y(10),BI &A(3,3),HH(3,3),W(3),C(39),B(3,3),TEXT(15 ) ,ACCUR(3),PSI(10),AK(9), BI &ALK(9) BI DOUBLE PRECISION CZ,ELLE,ELLK BI COMMON/ASDT/LAYER,NLAYS,M,R,Z,NU(10),ACCUR,LOAD.HOSTRS,NZEROS,H(9)BI &,K5(10),E(10),AL( 9) ,THICK(9),RADIUS(10 ) BI COMMON/STRDTA/STRESS(27),EPS(17),RLOW,ST,CT,L,ACC BI COMMON/CONST/CZ,ELLE,ELLK,ALMBDA BI COMMON/CNTING/F10M1,F100,F101,F11M2,F11M1,F110,F111 BI COMMON/TAPE/NOUT BI CHARACTER*14 FILEN CHARACTER*80 SITE CHARACTER*1 KNOWN CHARACTERS CHANGE DIMENSION D(10),D12(10),D21(10),D34(10),E12(10),E21(10),AX(10), &AY(10).DEPTH(10),ETA(10),DISP(10),DIFF(10),DISM(10),PECENT(10), &E12MU0),E2M(10),E1T(10),E2T(10),112(10),E1C(10) DATA NBLANK,ISTRSS,IREF1.IREF2/ BI &* t ,UR , ,'UT ', ,'UZ , ,SRR, >SITi ,'SZZ, ,SRT,SRZ, ,STZ ,ERRBI &, ETT\ , EZZ, ,ERT, ,ERZ, ,ETZ, ,UX ,UY , ,SXX,SXY, ,SXZ ,'SYYBI &, 'SYZ', ,EXX', ,EXY, ,'EXZ', ,EYY, ,EY, LOAD, ,'SIRS/ BI DATA IVER1,IVER2/1,2,3,6,7,13,14,4,5,8,9,10,11,12,15,16,17/ BI BEGIN PROGRAM STATEMENTS WRITE(*,8000) 8000 FORMAT(1,6X,THIS IS A SELF-ITERATIVE AND INTERACTIVE PROGRAM',/ &,7X,SEED MODULI ARE CALCULATED USING PREDICTION EQUATIONS FROM',/ &,7X,THE MODIFIED DYNAFLECT DEFLECTION TESTING SYSTEM *,/,7X,BI &SAR IS THEN USED TO COMPUTE DEFLECTIONS WHICH ARE COMPARED WITH,/ &,7X,MEASURED DEFLECTIONS : THE USER THEN ADJUST MODULI TO MATCH, &/,7X,FIELD DEFLECTIONS AS REQUIRED,//,IX,ENTER A NAME FOR YOUR & OUTPUT FILE TO BE COPIED TO (10 CHARACTERS OR LESS),/,IX, &==>,$) 463 ono noon non non 464 OUTPUT FILE READ(*,8001) FILEN 8001 FORMAT(A) WRITE(*,8001) FILEN N0T=6 N0UT=2 OPEN(UNIT=NOT,FILE=FILEN,STATUS=NEW) OPEN(UNIT=NOUT,FILE=1:BIS.TXT',STATUS=NEW) ACCUR(l)=1.0E-04 BI ACCUR(2)=1.0E-4 BI ACCUR(3)1.0E-3 BI ACC=ACCUR(1) BI V2=l.414214 BI WRITE(NOT,7001) 7001 FORMATC/,76(=),/,76 C ),/,2X,'DYNAFLECT EVALUATION OF LAYER & MODULI IN ASPHALT PAVEMENT SYSTEMS ,/,76( ),/,76(=)///) BI READ TEXT AND DATE CARD BI BI WRITE(*,8002) 8002 FORMATC/,2X,ENTER NAME OF TEST SITE, MILEPOST AND TEST DATE ') READ (* ,8003) SITE 8003 FORMAT(A80) WRITE(*,8003)SITE WRITE(NOT,8003) SITE READ NUMBER OF SYSTEMS AND SET LOOP READ DEFLECTIONS AND THICKNESSES 8004 8005 8006 8007 8008 NSYS = 1 ISMO = 0 IRED = 0 NPOS = 5 WRITE/*,8004) FORMAT(/,2X,WHAT IS READ(*,*)DISM(1) WRITE/*,8005) FORMATC/,2X,'WHAT IS READ(*,*)DISM(2) WRITE(*,8006) FORMAT(/,2X,'WHAT IS READ(*,*)DISM(3) WRITE(*,8007) FORMAT(/,2X,WHAT IS READ(*,*)DISM(4) WRITE/*,8008) FORMAT(/,2X,'WHAT IS READ(*,*)DISM(5) SENSOR 1 DEFLECTION ,DISM(1), SENSOR 2 DEFLECTION, DISM/2), SENSOR 3 DEFLECTION, DISM/3), SENSOR 4 DEFLECTION, DISM/4), SENSOR 5 DEFLECTION, DISM/5), IN MILS?) IN MILS?) IN MILS?) IN MILS? ) IN MILS? ) BI BI BI BI CHECK DEFLECTION CRITERIA 1 IF/DISM/1).LT.0.56.OR.DISM/1).GT.2.92) WRITE(*,62) IF(DISM/2).LT.0.56.OR.DISM/2).GT.2.92) WRITE/*,62) IF(DISM/3).LT.0.27.OR.DISM/3).GT.2.07) WRITE/*,62) q cj o non ooo 465 IF(DISM(4).LT.0.15.OR,DISM(4).GT.1.50) WRITE(*,62) IF(DISM(5).LT.0.05.OR,DISM(5).GT.1.00) WRITE(*,62) 62 FORMAT(//,1OX,NOTE THAT ONE OR MORE DEFLECTIONS NOT WITHIN THE & REQUIRED LIMITS,/,10X,'PREDICTED LAYER MODULI MAY BE IN ERROR , &/.10X,THEREFORE USE PREDICTIONS WITH CARE',//) THICKNESSES ARE READ HERE WRITE(*,8081) 8081 FORMAT(/,2X,WHAT IS ASPHALT CONCRETE THICKNESS, THICK(l), IN) READ ( * )THICK( 1) WRITE(*,8082) FORMAT(/,2X,WHAT IS BASE COURSE THICKNESS, THICK(2), IN?') READ(*,*)THICK(2) WRITE(*,8083) 8083 FORMAT(/,2X,WHAT IS STABILIZED SUBGRADE THICKNESS, THICK(3)?') READ(*,*)THICK(3 ) D(1) DISM(1)+DISM(2)-2*DISM(3) D34(2) = DISM(3)-DISM(4) CHECK DEFLECTION CRITERIA 2 IF(D(1).LT.0.09.OR,D(1).GT.0.85) WRITE(*,64) IF(D34(2).LT.0.12.OR.D34(2).GT.0.57) WRITE(*,64) 64 FORMAT(//,10X,NOTE THAT DEFLECTION CRITERIA ARE NOT MET ',/,10 &X,USE PREDICTED LAYER MODULI WITH CARE,//) T12(1) = THICK(1)+THICK(2) DISM(l) (DISM(l)+DISM(2))/2.0 DISM(2) = DISM(l) D12(1) = D(1)**("0.831) D21(1) = D(l)**(-0.805) E12(1) = 60611.0*D12(1) E2K1) = 59174.0*021(1) D34(2)=DISM(3)-DISM(4) D34(2)=D34(2)**(-1.0919) E12M(1) = (E12(l)+E21(l))/2.0 E(3) = 8754.1*D34(2) E(4) 5400.0/DISM(5) WRITE(*,9001) WRITE(NOT,9001) WRITE(*,9002)(DISM(I),1=1,NPOS) WRITE(NOT,9002)(DISM(I),1=1,NPOS) WRITE(*,9003) WRITE(NOT,9003) WRITEC*,9004) E12(1),E21(1),E12M(1),E(3),E(4) WRITE(NOT,9004) E12(1),E2K1),E12M(1),E(3),E(4) WRITE(*,9005) WRITE(NOT,9005) CHECK IF ASPHALT CONCRETE MODULUS IS KNOWN WRITE(*,'(A,S))DO YOU KNOW ASPHALT CONCRETE MODULUS, El? WRITE(*,'(A,S)')' (Y=YES, N=NO) ==> READ(*,701) KNOWN IF(KNOWN.EQ.y)KNOWN=Y IF(KNOWN.EQ.n)KNOWN=N o n o 466 IF (KNOWN.EQ.'N') THEN NLAYS = 3 M = NLAYS-1 DO 11 1=1,M NU(I) = 0.35 11 AK(I) = 0.0 E(l) = E12MC1) THICK(l) = T12<1) E (2) = E (3) THICK(2) = THICK(3) E (3 ) = E (4) NU(3) = 0.40 ELSE WRITE(*,9006) 9006 FORMAT(/,2X,'WHAT IS ASPHALT CONCRETE MODULUS, El, IN PSI?') READ(*,*) E(1) NLAYS = 4 M = NLAYS-1 DO 21 1=1,M NU(I) = 0.35 21 AK(I) = 0.0 E12(2) = E12(1)*T12(1) E1T(2) = E(1)*THICK(1) E12(2) = E12(2)-E1T(2) E12(2) = E12(2)/THICK(2) E2H2) = E21(l)**(0.33333) E2K2) = E21 (2) *T12 (1) E1C(1) = E(1)**(0.33333) E2T(2) = E1C(1)*THICK(1) E2H2) = E21 (2) -E2T (2) E21(2) = E21(2)/THICK(2) E2M(2) = E21(2)*E21(2) E2M(2) = E2M(2)*E21 (2) E(2) = (E12(2)+E2M(2))/2.0 NU(4) = 0.40 WRITE(*,9007) WRITE(NOT,9007) 9007 'FORMAT(//,12X,'PREDICTED LAYER MODULI FOR 4-LAYER SYSTEM &(*)//,4X,ASP. CONC.,2X,'BASE COURSE,3X,'AVERAGE, &SE,3X,SUBGRADE,/,8X,El,6X,E2(1),3X,E2(2),5X,E2 &8X,E4,/,4X,56(*)) WRITE(*,9008)E(1),E12(2),E2M(2),E(2),E(3),E(4) WRITE(NOT,9008)E(1),E12(2),E2M(2),E(2),E(3),E(4) 9008 FORMAT(4X,F8.0,2X,F8.0,IX,F8.0,2X,F8.0,3X,F8.0,2X,F8.0) ENDIF ,/,11X,43 3X,SUBBA ,8X,'E3', OUTPUT DATA AND PREDICTED MODULI WRITE(*,5001) WRITE(NOT,5001) WRITE(*,5002) WRITE(NOT,5002) IF(NLAYS.EQ.3) THEN WRITE(*,4002) E(1),NU(1),THICK(1) WRITE(NOT,4002) E(1),NU(1),THICK(1) WRITE(*,4003) E(2),NU(2),THICK(2) o o o 467 AK(J) = ALK(J)*(1.0+NU(J))/E(J) BI 50 CONTINUE BI C BI C OUTPUT OF ALL PHYSICAL DATA OF SYSTEM BI C AND LOADS BY CALLING IN SYSTEM. BI C BI CALL SYSTEM(ISYS,E,NU,THICK,AK,NLAYS,M,NLOAD,LDSTRS,HOSTR,ALK, BI & RADIUS,X,Y,PSI,ISMO,IRED) BI IF(.NOT.NZEP.AND..NOT.NZEQ) GO TO 430 BI C BI C CALCULATION OF CONSTANTS USED IN SUBROU- BI C TINE MATRIX TO BUILT UP VARIOUS MATRICES BI C BY CALLING IN MACON1. BI C BI CALL MACON1(ISMO,ALK,NEWSYS) BI 60 IF(NEWSYS.EQ.O) GO TO 70 BI CALL SYSTEM(ISYS,E,NU,THICK,AK,NLAYS,M,NLOAD,LDSTRS,HOSTR,ALK, BI & RADIUS,X.Y.PSI,ISMO,IRED) BI C BI C READ STRESSES,STRAINS AND DISPLACEMENTS BI C TO BE CALCULATED. BI C BI 70 DO 75 1=1,27 75 REQEST(I)=NBLANK REQEST(1)=ISTRSS(1) REQEST(2)=ISTRSS(2) REQEST(3)=ISTRSS(3) DO 90 1=1,27 IF(REQEST(I).EQ.NBLANK) GO TO 80 IF(REQEST(I).NE.ISTRSS(I)) WRITE(NOUT,9070) ISTRSS(I) AID(I)=.TRUE. GO TO 90 80 AID(I)=.FALSE. 90 CONTINUE C BI C CONSYS DETERMINES FOR EACH SYSTEM WHICH BI C STRESSES,STRAINS AND DISPLACEMENTS WILL BI C BE CALCULATED. BI C BI CALL CONSYS(AID,NZEP,NZEQ,N,L) BI BI READ NUMBER OF POSITIONS AND SET LOOP BI ----BI 100 NPOS = 5 LAYER = 1 DO 400 IPOS=l,NPOS BI DEPTH(IPOS) = 0.001 ETA(IPOS) = 0.0 AX (1) = 0.0 AY (1) 6.0 AX(2) = 0.0 AY(2) = 6.0 AX(3) = 4.0 AY(3) = 0.0 AX ( 4) = 16.0 AY(4 ) = 0.0 n n n non 468 AX(5) = 48.0 AY(5) = 0.0 N2 = N BI L2 L BI DO 110 1=1,3 BI DO 110 J=l,3 BI 110 A(I,J )=0.0 BI BI READ POINT COORDINATES AND LAYERNUMBER. BI BI ETA(IPOS)=.0174533*ETA(IPOS) BI IF(NLAYS.EQ.l) LAYER=1 BI WRITE(NOUT,9090) IPOS,LAYER,AX(IPOS),AY(IPOS),DEPTH(IPOS) BI TMIN=1.0E+10 BI IF(NLAYS.EQ.1) GO TO 130 BI J=LAYER+1 BI J=MIN0(J,M) BI DO 120 1=1,J BI IF(THICK(I).LT.TMIN) TMIN=THICK(I) BI 120 CONTINUE BI 130 UX=0.0 BI UY=0.0 BI UZ=0.0 BI MU=NU(LAYER) BI FT=(1.0+MU)/E(LAYER) BI BI SET LOOP FOR NUMBER OF LOADS. BI BI DO 330 1=1,NLOAD BI DO 140 J-1,17 BI 140 INT(J)=0.0 BI DO 150 J=1,27 BI 150 STRESS(J)=AID(J) BI IF(NLAYS.EQ.1) GO TO 160 BI c SI C CALCULATION OF CONSTANTS NEEDED FOR THE BI C EVALUATION OF THE CHARACTERISTIC FUNCTI- BI C ONS IN MATRIX BY CALLING IN MA2CON. BI C MA2CON. BI c BI CALL MA2C0N(TMIN,I,ISMO,ALK) BI c BI C DETERMINATION OF POINT COORDINATES IN THE BI C CYLINDRICAL COORDINATE SYSTEM WITH LOAD- BI C AXIS AS AXIS OF SYMMETRY. BI C BI 160 IF(X(I) .EQ. AX(IPOS). AND Y(I) EQ. AY(IPOS)) GO TO 170 BI THETA=ATAN2((AY(IPOS)-Y(I)),(AX(IPOS)-X(I)))-PSI(I) BI GO TO 180 BI 170 THETA=ETA(IPOS)-PSI(I) BI 180 RADDIS=SQRT ( ( AX( IPOS ) -X (I ) )**2+(AY (IPOS)-Y(I) )**2) BI WRITE(NOUT,9100) I,RADDIS,THETA BI R=RADDIS/RADIUS(I) BI Z=DEPTH(IPOS)/RADIUS(I) BI IF(NLAYS.EQ.1) GO TO 230 BI 190 IF(LAYER.GT.1) GO TO 210 BI o o o o 469 IF(Z.GT.-ACCUR(1).AND.Z.LT.(H(1)+ACCUR(1))) GO TO 230 BI 200 WRITE(NOUT,9110) BI GO TO 400 BI 210 IF(LAYER.LT.NLAYS) GO TO 220 BI IF(Z. GT (H(M) -ACCUR( 1) ) ) GO TO 230 BI GO TO 200 BI 220 IFCZ.GT.(H(LAYER-1)-ACCUR(1)).AND.Z.LT.(H (LAYER)+ACCUR(1)BI & )) GO TO 230 BI GO TO 200 BI 230 RADI=RADIUS(I) BI LOAD=LDSTRS(I) BI HOSTRS=HOSTR(I) BI RLOW=R.LT.ACCUR(1) BI ST=SIN(THETA) BI CT=COS(THETA) BI c BI C CONPNT DETERMINES FOR EACH POINT-LOAD BI C CONFIGURATION WHICH INTEGRALS HAVE TO BE BI C CALCULATED. BI c BI CALL CONPNT(R,HOSTRS,LOAD,Z,N2,L2) BI IF(LAYER.NE.1) GO TO 250 BI CZ = DBLE(Z) BI IF(Z.LT.ACCUR(1).AND.ABS(R-1.0).LT.ACCUR(1)) GO TO 240 BI c BI C ASYMPT DETERMINES THE LIPSCHITZ-HANKEL BI C INTEGRALS NEEDED FOR THE ASYMPTOTIC PART BI C OF THE INTEGRALS,FOR POINTS IN THE TOP- BI C LAYER ONLY. BI c BI CALL ASYMPT(R,ACCUR(1)) BI GO TO 250 BI C BI C FOR POINTS AT THE RIM OF THE LOAD THE BI C LIPSCHITZ-MANKEL INTEGRALS CAN BE GIVEN BI C DIRECTLY. BI C BI 240 F10M1 = 0.63662 BI F100 = 0.5 BI F11M1 =0.5 BI F11M2 = 0.424413 BI FIO 1 = 0.0 BI F110 = 0.0 BI Fill = 0.0 BI BI COMPUTATION OF THE REQUIRED INTEGRALS BY BI CALLING IN GENDAT AND INGRAL BI BI 250 INTT =0 BI DO 260 J = 1,17 BI INT(J) = 0.0 BI 260 CONTINUE BI DO 270 J = 1,10 BI INTV(J) =0 BI K = IVER2CJ) BI IF(.NOT.EPS(K)) GO TO 270 BI o o o 470 12 2 20 30 C- C C C C C C C C- 40 WRITE(NOT,4003) E(2),NU(2),THICK(2) WRITE(*,4004) E(3),NU(3) WRITE(NOT,4004) E(3),NU(3) ELSE DO 12 1=1,M WRITE(*,5003) I,E(I),NU(I),THICK(I) WRITE(NOT,5003) I,E(I),NU(I),THICK(I) WRITE(*,5004) NLAYS,E(NLAYS),NU(NLAYS) WRITE(NOT,5004) NLAYS,E(NLAYS),NU(NLAYS) ENDIF READ NUMBER OF LOADS AND THEIR PARAMETERS BI NLOAD = 2 NZEP = .FALSE. BI NZEQ = .FALSE. BI IDENT = IREF1 DO 30 1=1,NLOAD BI LDSTRS(I) = 500.0 RADIUS(I) =4.5 HOSTR(I) =0.0 PSI(I) = 0.0 XCI) = 0.0 PSI(I)=.0174533*PS1(1) BI IF(LDSTRS(I).GT.ACCUR(1)) NZEP= .TRUE. BI IF(HOSTRd) .GT.ACCUR(l)) NZEQ = .TRUE. BI IF(IDENT.EQ.IREF1) GO TO 20 BI IF(IDENT.NE.IREF2) WRITE(NOUT,9040) LDSTRS(I),HOSTR(I) BI GO TO 30 BI LDSTRS(I) = LDSTRS(I)/(3.14159*RADIUS(I)*RADIUS(I)) BI HOSTR(I) = HOSTR(I)/(3.14159*RADIUS(I)*RADIUS(I)) BI CONTINUE BI Y(1) = -10.0 Y(2) = 10.0 B1 TEST ON OBVIOUS MISTAKES IN SYSTEMS DATA-BI CARDS. BI WHEN IRED > 0 THE REDUCED SPRINGCOMPLIAN- BI CE WAS READ. BI A NON-VANISHING SLIPRESISTANCE IS SUBSTI- BI TUTED TO PREVENT RIGID-BODY MOTION OF THE BI TOPLAYERS BI ----BI DO 50 J = 1,NLAYS BI IF((1.0-NU(J)).LT.ACCUR(1)) GO TO 410 BI IF(E(J).LT.ACCUR(1)) GO TO 420 BI IF(J.EQ.NLAYS) GO TO 50 BI IF(IRED.EQ.0) GO TO 40 BI ALK(J) = AK(J) BI IF(ALK(J).LT.1000.0.OR..NOT.NZEQ) GO TO 50 BI ALK(J) = 1000.0 BI AK(J) = 1000.0 BI GO TO 50 BI ALK(J) = AK(J)*E(J)/(1.0+NU(J)) BI IF(ALK(J).LT.1000.0.OR..NOT.NZEQ) GO TO 50 BI ALK(J) = 1000.0 BI 471 INTV(J) = K BI INTT = INTT+1 BI 270 CONTINUE BI IF(INTT.EQ.O) GO TO 280 BI IF (NLAYS NE 1) CALL GENDATd, NZEROS.R, ACC) BI CALL INGRAL(2,INTV,INTT,INT) BI 280 INTT =0 BI DO 290 J = 1,7 BI INTV(J) =0 BI K = IVERl(J) BI IF(.NOT.EPS(K)) GO TO 290 BI INTV(J) = K BI INTT = INTT+1 BI 290 CONTINUE BI IFCINTT.EQ.0) GO TO 300 BI IF(NLAYS.NE.1) CALL GENDATCO,NZEROS.R,ACC) BI CALL INGRAL(1,INTV,INTT,INT) BI 300 PSIO = PSI(I) BI c BI C CALC COMPUTES AND OUTPUTS THE STRESSES, BI C STRAINS AND DISPLACEMENTS,INDUCED BY EACH BI C LOAD SEPARATELY. BI C BI CALL CALC(INT,V,R,MU,RADI,FT,LOAD,HOSTRS,PSIO,Z) BI IF(.NOT.N2) GO TO 330 BI C BI C COMPUTATION AND SUMMATION OF CARTESIAN BI C COORDINATES.THE USED COORDINATE SYSTEM IS BI C THE ONE WHEREIN POINTCOORDINATES WERE BI C STATED. BI c BI UZ =UZ+V(3) BI IF(ABS(RADDIS).LT.ACCUR(I)) GO TO 310 BI CT = (AX(IPOS)-X(I))/RADDIS BI ST = (AY(IPOS)-Y(I))/RADDIS BI GO TO 320 BI 310 CT =COS(ETA) BI ST =SIN(ETA) BI 320 CT2 =CT*CT BI ST2 =ST*ST BI STCT =ST*CT BI A(l,1)=A(1,1)+V(4)*CT2+V(5)*ST2-2.0*V(7)*STCT BI A(1,2)=A(1,2)+V(7)*(CT2-ST2)+(V(4)-V(5))*STCT BI A(1,3)=A(1,3)+V(8)*CT-V(9)*ST BI A(2,1)=A(1,2) BI A(2,2)=A(2,2)+V(4)*ST2+V(5)*CT2+2.0*V(7)*STCT BI A(2,3)=A(2,3)+V(8)*ST+V(9)*CT BI A(3,1)=A(1,3) BI A(3,2)=A(2,3) BI A(3,3)=A(3,3)+V(6) BI UX =UX+V(1)*CT-V(2)*ST BI UY =UY+V(1)*ST+V(2)*CT BI 330 CONTINUE BI TRACE=A(1,1)+A(2,2)+A(3,3) BI AB (1.0+MU)/E(LAYER) BI AC =MU* TRACE/E(LAYER) BI 472 DO 350 1=1,3 El DO 340 J=1,3 BI B (I,J)=AB*A(I, J) BI IF(I.NE.J) GO TO 340 BI B(I,J)=B(I,J)-AC BI 340 CONTINUE BI 350 CONTINUE BI C BI C OUTPUT FOR TOTAL STRESSES,STRAINS AND BI C DISPLACEMENTS BY THREE TIMES CALLING IN BI C OUTPUT. BI C BI WRITE(NOUT,9120) BI EPS(1)STRESS(18) BI EPS(2)STRESS(21) BI EPS(3)STRESS( 6) BI EPS(4)STRESS(22) BI EPS(5)STRESS(20) BI EPS(6)STRESS(19) BI C(1)A(1,1) BI C(2)=A(2,2) BI C(3)=A(3,3) BI C(4)=A(2,3) BI C(5)A(1,3) BI C(6)=A(1,2) BI CALL OUTPUT(EPS,C,6,1) BI EPS(1)=STRESS(23) BI EPS(2)=STRESS(26) BI EPS(3)STRESS(12) BI EPS(4)STRESS(27) BI EPS(5)STRESS(25) BI EPS(6)=STRESS(24) BI C(1)=B(1,1) BI C(2)=B(2,2) BI C(3)=B(3,3) BI C(4)=B(2,3) BI 473 360 C c c c c c c c c c c 370 380 C C C C 390 & & C(5)=B(1,3) C(6)=B(1,2) CALL OUTPUT(EPS,C,6,2) EPS(1)=STRESS (16 ) EPS(2)STRESS(17) EPS(3)=STRESS( 3) C (1)=UX C(2 )=UY C(3)=UZ DISP(IPOS)=UZ*1000.0 CALL OUTPUT(EPS, C, 3,3 ) IF(.NOT.L2) GO TO 400 BI BI BI BI BI BI BI BI BI BI BI BI JACOBI COMPUTES PRINCIPAL VALUES AND BI DIRECTIONS OF TOTAL STRESSES AND STRAINS. BI THE PRINCIPAL VALUES ARE SORTED ACCORDING BI TO MAGNITUDE BY CALLING IN ESORT. BI BI CALL JACOBI(A,HH,3,3,l,W,IQ) CALL ESORT(A,HH,3,3,l,W,IQ) BI BI -BI DETERMINATION OF MAX.SHEAR STRESSES AND BI STRAINS WITH THEIR DIRECTIONS AND DETERMI-BI NATION OF MIDPOINTS OF THE MOHRS CIRCLE. BI BI DO 370 J-1,3 C(J )=AB*A(J,J)-AC C(J+ 5)=(HH(J,1)-HH(J,3))/V2 C(J+ 9)=(HH(J, 1)+HH(J,3))/V2 C(J+14)=(HH(J,1)-HH(J,2))/V2 C(J+18)=(HH(J,1)+HH(J,2))/V2 C(J+23)=(HH(J,2)-HH(J,3))/V2 C(J+27)=(HH(J,2)+HH(J,3>)/V2 CONTINUE C( 4)=0.5*(A(1,1)-A(3,3)) C( 9)=0.5*(A(1,1)+A(3,3)) C(13)=0.5*(A(1,1)-A(2,2)) C(18)=0.5*(A(1,1)+A(2,2)) C(22)=0.5*(A(2,2)-A(3,3)) C(27)=0.5*(A(2,2)+A(3, 3)) C( 5)-0.5*(C(l)-C(3)) C(14)=0.5*(C(1)-C(2)) C(23)=0.5*(C(2)-C(3)) IF(C(13).GT.C(22)) GO TO 390 DO 380 1=1,9 C(1+30)=C(1+12) C(1+12)=C(1+21) C(1+21)=C(1+30) CONTINUE BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI BI OUTPUT FOR PRINCIPAL STRESSES,ETC,MAXIMUM BI SHEAR STRESSES,ETC AND STRAIN ENERGIES. BI BI WRITE(NOUT,9130)A(1,1),C(1),HH(1,1),HH(2,1),HH(3,1), BI A(2,2),C(2),HH(1,2),HH(2,2),HH(3,2), BI A(3,3),C(3),HH(1,3),HH(2,3),HH(3,3 ), BI 474 & (C(I),I=4,30) BI BI BI BI BI BX = (A(1,1)*C(1)+A(2,2)*C(2)+A(3,3)*C(3))*0.5 BY = 0.6666667*AB*(C(4)*C(4)+C(13)*C(13)+C(22)*C(22) WRITE(NOUT,9200) BX,BY 400 CONTINUE WRITE(*,9135) WRITE(NOT,9135) DO 405 I=l,NPOS DIFF(I)=DISP(I)-DISM(I) PECENT(I)3DIFF(I)/DISM(I) PECENT(I)100*PECENT(I) WRITE(*,9137) I,DISM(I),DISP(I),DIFF(I),PECENT(I) 405 WRITE(NOT,9137) I,DISM(I),DISP(I),DIFF(I),PECENT(I) GO TO 460 410 WRITE(NOUT,9140) J BI GO TO 440 BI 420 WRITE(NOUT,9180) J BI GO TO 440 BI 430 WRITE (NOUT,9190) BI 440 NPOS=5 C BI C FOR SYSTEMS FOR WHICH IT IS CLEAR THAT BI C MISTAKES OCCUR IN THE INPUTCARDS,THE BI C REQUEST AND POINT INPUT CARDS ARE SKIPPED.BI C PROGRAM PROCEEDS BY TAKING NEXT SYSTEM. BI C BI 460 WRITE (* (A, $ ) ) DO YOU WANT TO CHANGE ANY E-VALUE?' WRITE(*, (A,$)' ) (Y=YES, N=NO) 33> READ(*,701) CHANGE 701 FORMAT(A) IF(CHANGE.EQ.'y')CHANGE3Y IF(CHANGE.EQ.'n')CHANGE3N IF(CHANGE.EQ.'N')GO TO 705 IF (NLAYS.EQ.3) THEN WRITE(*,601) 601 FORMAT(/,2X, INPUT NEW COMPOSITE E12 VALUE, E12N, IN PSI,/,2X, OTHERWISE ENTER THE PREDICTED AVERAGE E12 VALUE IN PSI,//,1X, &' 33> ) READ(*,*) E12N WRITE(*,*) E12N WRITE(*,602) 602 FORMAT(/,2X,'INPUT NEW STABILIZED SUBGRADE MODULUS, E3N, IN PSI,/ &,2X,'OTHERWISE ENTER THE PREDICTED E3 VALUE IN PSI,//,IX,==> ) READ(*,*) E3N WRITE(*,*) E3N WRITE(*,603) 603 FORMAT(/,2X,INPUT NEW SUBGRADE MODULUS, E4N, IN PSI,/,2X,OT &HERWISE ENTER THE PREDICTED E4 VALUE IN PSI',//,IX,'==> ) READ(*,*) E4N WRITE(*,*) E4N E(1)=E12N E(2)=E3N E(3)=E4N WRITE!*,306) WRITE(NOT,306) WRITE(*,5002) 475 WRITE(NOT,5002) WRITE(*,4002) E(1),NU(1),THICK(1) WRITE(NOT,4002) E(l),NU(1),THICK(1) WRITE(*,4003) E(2),NU(2),THICK(2) WRITE(NOT,4003) E(2),NU(2),THICK(2) WRITE(*,4004) E(3),NU(3) WRITE(NOT,4004) E(3),NU(3) ELSE WRITE(*,604) 604 FORMAT(/,2X, INPUT NEW ASPHALT CONCRETE MODULUS, E1N, &X, OTHERWISE ENTER KNOWN El VALUE IN PSI,//,IX,'==> READ(*,*) E1N WRITE(*,*) E1N WRITE(*,605) 605 FORMAT(/,2X, INPUT NEW BASE COURSE MODULUS, E2N, IN PSI &THERWISE ENTER THE PREDICTED E2 AVERAGE VALUE IN PSI,//,IX &) READ(*,*) E2N WRITE(*,*) E2N WRITE(*,602) READ(*,*) E3N WRITE(*,*) E3N WRITE(*,603 ) READ(*,*) E4N WRITE(*,*) E4N E(1) = E1N E(2) = E2N E(3) = E3N E(4) = E4N WRITE(*,306) WRITE(NOT,306) WRITE(*,5002) WRITE(NOT,5002) DO 15 1=1,M WRITE(*,5003) I,E(I),NU(I),THICK(I) 15 WRITE(NOT,5003 5 I,E(I),NU(I),THICK(I) WRITE(*,5004) NLAYS,E(NLAYS),NU(NLAYS) WRITE(NOT,5004) NLAYS,E(NLAYS),NU(NLAYS) ENDIF IF(CHANGE.EQ.'Y)GO TO 2 705 WRITE(*,6001) WRITE(NOT,6001) WRITE(*,5002) WRITE(NOT,5002) IF(NLAYS.EQ.3) THEN WRITE(*,4002) E(1),NU(1),THICK(1) WRITE(NOT,4002) E(1),NU(1),THICK(1) WRITE(*,4003) E(2),NU(2),THICK(2) WRITE(NOT,4003) E(2),NU(2),THICK(2) WRITE(*,4004) E(3),NU(3) WRITE(NOT,4004) E(3),NU(3) ELSE DO 13 1=1,M WRITE(*,5003) I,E(I),NU(I),THICK(I) 13 WRITE(NOT,5003 ) I,E(I),NU(I),THICK(I) WRITE(*,5004) NLAYS,E(NLAYS),NU(NLAYS) IN PSI,/, ) /,2X, O => 476 WRITE(NOT,5004) NLAYS,E(NLAYS),NU(NLAYS) ENDIF WRITE(*,9136) WRITE(NOT, 9136) WRITE(*,9137)(I,DISM(I),DISP(I),DIFF(I),PECENT(I),I=l,NPOS) WRITE(NOT,9137)(I,DISM(I),DISP(I),DIFF(I),PECENT(I),I=l,NPOS) STOP 9001 FORMAK//, 4X,'MEASURED DYNAFLECT DEFLECTIONS IN MODIFIED SYSTE &M / ,4X, (AN AVERAGE VALUE OF DI & D2 IS USED IN THE ANALYSIS),/ &,4X,54('*),/,10X,DI,6X,'D2',6X,'D3',6X,'D4',6X,'D5',/) 9002 FORMAT(6X,5(F6.3,2X)////) 9003 FORMAT(/,4X, PREDICTED LAYER MODULI USING DEVELOPED EQUATIONS = &,//, COMPOSITE MODULUS AVERAGE SUBBASE SUBGRADE ,/ &,' EQN1 EQN2 MODULUS MODULUS MODULUS &E12(1) E12(2) E12 E3 E4 ,/,70(_),/) 9004 FORMAT(2X,3(F9.0,2X),2(F8.0,2X)) 9005 FORMAT(/,5X, WHERE DEFLECTIONS ARE IN MILS AND MODULI IN PSI,// &/,4X,66(=),/) 5001 FORMAK////,16X,'INITIAL PAVEMENT PARAMETERS,/,11X,33(*),/) 306 FORMAT(//,16X,'MODIFIED PAVEMENT PARAMETERS,/,11X,34(*),/) 6001 FORMAK////,16X,'FINAL PAVEMENT PARAMETERS,/,11X,33(*),/) 5002 FORMAK/,6X,'LAYER',4X,'MODULUS,3X,'POISSON', ,'S,3X,THICKNE &SS,/,7X,'NO.,7X,'PSI',7X,'RATIO',7X,IN.,/,6X,40(*)) 4002 FORMAK6X,'1,2,6X,F8.0,5X,F4.2,5X,F6.2) 4003 FORMAT(7X,3,7X,F8.0,5X,F4.2,5X,F6.2) 4004 FORMAT(7X,4,7X,F8.0,5X,F4.2,5X,'SEMI-INF',/) 5003 FORMAT(7X,I2,6X,F8.0,5X,F4.2,5X,F6.2) 5004 FORMAT(7X,I2,6X,F8.0,5X,F4.2,5X,'SEMI-INF',/) 9010 FORMAK15A4,12,13,15) BI 9020 FORMAT(1H1,25(/),15X,15A4,12,1H/,12,1H@,14) BI 9030 FORMAT(12,13,11) BI 9040 FORMAK NOTE THAT ,E12.6, AND ,E12.6, WILL BE CONSIDERED TO BBI &E LOADS IN STRESS UNITS) BI 9050 FORMAT(4E12,6) BI 9060 FORMAK26A3,A2) BI 9070 FORMAK' NOTE THAT INCORRECT SPELLING HAS NOT STOPPED THE EVALUATIBI &ON OF STRESS,4X,A3) BI 9080 FORMAK12,4E12.6) BI 9090 FORMAK1H1,///52X,'POSITION NUMBER ,12//54X,LAYER NUMBER .I2//BI &55X,COORDINATES//46X,'X',11X,Y,11X,Z/40X,3E12.4) BI 9100 FORMAK/2IX,'DISTANCE TO LOAD-AXIS(,12,'),34X,THETA/25X,E12.4,BI &4IX,E12.4/) BI 9110 FORMAK//,30X,'THIS POSITION HAS BEEN OMITTED SINCE THE LAYER NUMBBI &ER IS INCORRECT) BI 9120 FORMAK/3OX, XX 10X, YY 10X, ZZ' 10X, YZ 10X, XZ 10X, XY 10X,BI &UX,10X,'UY',10X,'UZ') BI 9130 FORMAK/ PRINCIPAL VALUES AND DIRECTIO NBI & S OF TOTAL STRESSES AND STRAIN S/15X,NOBI &RMAL,9X,'NORMAL',9X,'SHEAR',10X,'SHEAR',13X,X,14X,Y,14X,Z/1BI &5X,'STRESS',9X,'STRAIN',9X,'STRESS,9X,'STRAIN',9X,'COMPONENT',6X,BI &COMPONENT,6X,'COMPONENT'/ MAXIMUM',2E15.3,30X,3F15.3/ MINIMAXBI &,2E15.3,30X,3F15.3/ MINIMUM,2E15.3,30X,3F15.3/ MAXIMUM,30X,2E1BI &5.3,3F15.3/8X,E15.3,45X,3F15.3/' MINIMAX,30X,2E15.3,3F15.3/8X, BI &E15.3,45X,3F15.3/ MINIMUM,30X,2E15.3,3F15.3/8X,E15.3,45X,3F15.3)BI 9135 FORMAK//,1OX,'COMPARISON BETWEEN PREDICTED AND MEASURED DEFLECTIO &NS,/,7X,57(*),/,4X, SENSOR MEASURED PREDICTED DIFFE REFERENCES 1. AASHTO, Methods of Sampling and Testing, American Association of State Highways and Transportation Officials, Washington, D.C., 1984. 2. Acum, W.E.A., and Fox, L., "Computation of Load Stresses in a Three-Layer Elastic System," Geotechnique, Vol. 2, 1951, pp. 293-300. 3. Ahlborn, G., "Elastic Layered Systems with Normal Loads," Research Report, Institute of Transportation and Traffic Engineering, University of California-Berkeley, 1972. 4. Ahlvin, R.G., and Ulery, H.H., "Tabulated Values for Determining the Complete Pattern of Stresses, Strains and Deflections Beneath a Uniform Circular Load on a Homogeneous Half Space," Highway Research Board Bulletin 342, HRB, Washington, D.C., 1962. 5. Alam, S., and Little, D.N., "Evaluation of Fly Ash and Lime-Fly Ash Test Sites Using a Simplified Elastic Theory Model and Dynaflect Measurements," Transportation Research Record 1031, TRB, Washington, D.C., 1985, pp. 17-27. 6. Anani, B.A., An Evaluation of In-Situ Elastic Moduli From Surface- Deflection Basins of Multi-Layer Flexible Pavements, Ph.D. Dissertation, The Pennsylvania State University, 1979, 189 pp. 7. Ashton, J.E., and Moavenzadeh, E., "Analysis of Stresses and Dis placements in a Three-Layer Viscoelastic System," Proceed- ings, Second International Conference on the Structural Design of Asphalt Pavements, University of Michigan, August 7-11, 1967, pp. 209-219. 8. ASTM, Annual Book of ASTM Standards, Section 4, Vol. 04.03, American Society of Testing and Materials, Philadelphia, Pennsylvania, 1987. 9. ASTM, "Standard Method of Indirect Tensile Test for Resilient Modulus for Bituminous Mixtures," ASTM Test Designation D4123-82, Annual Book of ASTM Standards, Vol. 04.03, ASTM, Philadelphia, Pennsylvania, 1987, pp. 671-675. 478 479 10. 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He received his elementary education in the Kumasi public schools. His secondary education was completed at T.I. Ahmadiyya Secondary School in Kumasi. In 1973 and 1975, respectively, he passed the Ordinary ("0") and Advanced ("A") Level General Certificate of Education (GCE) examina tions, organized by the West African Examinations Council. In October 1975, he gained admission into the University of Science and Technology (UST), Kumasi, Ghana, graduating with honors in August 1979 with a Bachelor of Science degree in civil engineering. From October 1979 to August 1981 he was based at the Institute of Foundation Engineering and Soil Mechanics of the Federal Institute of Technology, Zurich, Switzerland, where he pursued postgraduate research studies in soil engineering. In November 1980, he was awarded a Swiss Government Exchange scholarship to conduct research work on the engi neering classification of red tropical soils (latentes). In August 1981, he began studies towards a master's degree in civil engineering at Arizona State University, Tempe, Arizona, while holding a half-time assistantship position with the Arizona Transportation Research Center of the Arizona Department of Transportation (ADOT). He was awarded the Regents Graduate Academic scholarship at Arizona State University for the 1983-84 academic year. For his master's thesis, he developed an in situ penetration test for the study of collapsible 491 492 soils. He received a Master of Science degree in civil engienering in August 1984. Since August 1984, he has had a half-time graduate research assis- tantship in the civil engineering department, University of Florida, while studying for the degree of Doctor of Philosophy. His areas of major concentration were geotechnical engineering, pavements/materials, and applied statistics. During this time he was primarily involved with the Florida Department of Transportation (FDOT) sponsored research on structural characterization of in-place pavement materials using in situ nondestructive and penetration tests. He received the University of Florida President's Recognition Award in April 1985. He was also awarded an American Public Works Association (APWA) Travel Grant Award to participate in the 1986 APWA International Congress and Equipment Show in New Orleans, Louisiana, from September 20 to 25, 1986. He has also participated in other important technical meetings, such as the 1986 In Situ Conference at Virginia Tech, the 1987 annual meeting of the Transportation Research Board in Washington, DC, and the VIII Panamerican Conference on Soil Mechanics and Foundation Engineering, held in Cartagena, Colombia, in August 1987. In 1985, he passed the Engineer Intern examination towards the professional engineer registration. He is a member of Tau Beta Pi, an Engineering Honor Society; and Phi Beta Delta, an Honor Society for International Scholars. He is also a member of the American Society of Civil Engineers, Transportation Research Board, American Public Works Association, and the Institute of Transportation Engineers. He is cur rently author and co-author of about ten technical publications. I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. Byron E. Ruth, Chairman Professor of Civil Engineering I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. Frank C. Townsend Professor of Civil Engineering I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. strJ JohnU.1 Davidson Professor of Civil Engineering Sciences I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. Mang Tia i Associate PWfessor of Civil Engineering I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. sfoyHi pa Janesi L. Eades Associate Professor of Geology I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. Daniel P. Spangler Associate Professor of Geology This dissertation was submitted to the Graduate Faculty of the' College of Engineering and to the Graduate School and was accepted as partial fulfillment of the requirements for the degree of Doctor of Philosophy. December 1987 Dean, lege of Engineering Dean, Graduate School UF Libraries: Digital Dissertation Project Page 2 of 2 Internet Distribution Consent Agreement In reference to the following dissertation: AUTHOR: Badu-Tweneboah, Kwasi TITLE: Evaluation of layer moduli in flexible pavement systems using nondestructive and penetration testing methods / (record number: 1036909) PUBLICATION DATE: 1987 . i, KW/Vsi as copyright holder for the aforementioned dissertation, hereby grant specific and limited archive and distribution rights to the Board of Trustees of the University of Florida and its agents. I authorize the University of Florida to digitize and distribute the dissertation described above for nonprofit, educational purposes via the Internet or successive technologies. This is a non-exclusive grant of permissions for specific off-line and on-line uses for an indefinite term. 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