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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 230F and 410F 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