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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