In-situ validation of mechanistic pavement finite element modeling

Abstract

A three-dimensional (3D) finite element (FE) model simulating one of the pavement sections at the Virginia Smart Road was developed; convergence and accuracy were verified. On one hand, results of the FE model were compared against the layered theory; on the other hand, results of the FE model were compared against field-measured pavement responses. The comparison indicated that, in spite of conducting a convergence analysis to ensure accuracy of the FE solution, the resulting model and its analogue layered model may yield erroneous results. To improve the accuracy of the developed model, several modifications are necessary; some of which improved the predictions of the mechanistic model. A laboratory-calibrated time hardening model was successfully incorporated in the developed FE model to simulate time retardation of hot-mix asphalt (HMA) in the transverse direction, and fast relaxation of HMA in the longitudinal direction. In addition, the FE model was capable of predicting pavement surface damage and its partial recovery after load application. However, it has to be noted that anisotropic characteristic of HMA is a critical factor that must be considered to accurately simulate pavement responses in the lateral directions.