模量不均匀路基上的沥青路面动力响应研究

The main purpose of this study is to investigate the dynamic response of asphalt pavement supported by subgrade with non-uniform modulus. Firstly, the PFWD was employed to test the subgrade of Yabuli-Xuexiang highway, and the spatially nun-uniform characteristics of subgrade modulus were analyzed and summarized. Secondly, the dynamic coupling model of truck-pavement-non-uniform subgrade was proposed considering the movement of truck body, the viscoelastic performance of tire, the viscoelastic properties of asphalt pavement and the spatially nun-uniform characteristics of subgrade modulus. Finally, the effects of nun-uniform modulus, velocity and loading on the dynamic response of the asphalt pavement were discussed and analyzed. Numerical results show that: the nun-uniform subgrade has significant influences on the pavement dynamics. When a truck is running on the nun-uniform subgrade, the strain amplitude induced by the rear axle is about two times of that of the front axle. By increasing the rear axle loading from 100kN to 180kN, the strain amplitude increases from 62με to 109με. With the velocity increasing from 5km/h to 80 km/h, the strain amplitude may increase 1.3 times. By decreasing the nun-uniform modulus from 40MPa to 0 and increasing the nun-uniform ranges from 1m to 4m, the strain amplitude can increase 26% and 23%, respectively.