Modeling and Analysis of Stress-Dependency Coupling with Temperature-Sensitivity for Surface Layer of Semi-Rigid Base Asphalt Pavement

摘要

The dynamic modulus tests on 24 specimens of AC-20 were performed at six loading frequencies, three confining pressures and four temperatures, respectively. The values of parameters were obtained by fitting the K-θ model based on test results. A user subroutine incorporating stress-dependent behavior of asphalt concrete for the ABAQUS finite element (FE) model was written and validated. Then a three-dimensional (3D) FE pavement model was developed to investigate the pavement responses. The study analyzed the effects of stress-dependency coupling with temperature-sensitivity of the hot-mix asphalt (HMA) layer on pavement responses, including surface deflection, shear stress and tensile strain in the HMA layer, maximum principal stress at the bottom of the base layer, and compressive strain on top of the subgrade. The results showed that surface deflection and tensile strain in the HMA layer had significant temperature-sensitivity. Compared with loading frequency, the effects of temperature on stress-dependent modulus of the HMA layer and predicted pavement responses were greater. It was found that stress-dependent model resulted in greater predicted pavement responses in comparison to the linear model.