Numerical Simulation of Dynamic Performance of Highway Subgrade under Traffic Loads

According to the traffic load characteristics,the numerical simulation was carried out using the finite element software ABAQUS to simplify the subgrade under traffic load to a 3D model.The dynamic parameters of traffic load,s including static load,moving constant load and sinusoidal load,were simulated and analyzed by adopting pseudo static method.By using the existing constitutive relation of elasto-plastic soil,the finite element model of subgrade soil was established.By determining the parameters of mode,the numerical analysis and computation of the dynamic response of the subgrade soil under traffic load were carried out,thus the dynamic performance of the subgrade soil under traffic load was obtained.The results show that(1) the effect of loading on the road surface ranges from square of 8 m×8 m to 10 m×10 m,and the effect along the direction of the subgrade ranges from depth of 6 m to 8 m;(2) under moving load,dynamic response of pavement structure is larger than the response under static load,and the plastic strain increases significantly;(3) under sinusoidal load,the dynamic response of pavement structure changes little compared to that under moving load,and the effect of vehicle speed on the response of the structure is small.