This thesis presents the application of the stress-dependent National Cooperative Highway Research Program (NCHRP) Mechanistic Empirical Pavement Design Guide (MEPDG) model for resilient modulus, Mr, in dynamic finite element analyses of pavement systems loaded by vibratory rollers. The MEPDG model has been well established as an appropriate means for describing the stress-dependent Mr of a soil material. However, it has not been previously used in dynamic analyses of pavement systems and has been limited to static applications.;In this study, an iterative Matlab-Abaqus algorithm is developed based on equivalent linear strain dependent dynamic analysis procedures used in seismic analyses to determine stress-dependent Mr values for soil foundations undergoing dynamic vibratory loading from a vibratory roller compactor. The soil materials and lift thicknesses were modeled based upon previously compiled field data from sites in Florida. Iterative dynamic finite element analyses were performed using resulting stress values and iteratively updated Mr values that could spatially vary in the soil foundation to determine the force-deflection behavior of a vibratory roller on the soil. The force-deflection behavior results from the finite element analyses were then compared to the field data measured during mapping of compacted lifts in Florida by an instrumented vibratory compactor. The results of this study show similarities to results obtained from the field data, indicating that the proposed algorithm may be a feasible modeling procedure for dynamic loading of pavement systems. However, further investigations are required to develop the proposed model for use in the field.
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