沥青路面在半正弦荷载下的力学响应

研究轮胎/路面的接触印迹特征及随机荷载作用特点,采用ABAQUS软件构建路面结构三维有限元模型,对半正弦荷载作用下的沥青路面力学响应进行分析。结果表明,半正弦荷载作用下沥青路面的上面层和中面层出现应力应变集中,应力应变值随路面深度的增加而逐渐减小;沥青路面的竖向、横向及纵向应力最大值均出现在上面层,且竖向应力最大,横向应力次之,纵向应力最小;竖向、横向应变最大值出现在上面层,纵向应变最大值出现在上-中面层,且路面结构内部出现反复的纵向拉-压变形,这很可能是沥青路面轮迹带附近材料产生疲劳损坏的根本原因。另外,荷载作用时间和路面温度对沥青路面应变的影响要大于其对应力的影响,路面温度的升高导致应变增大且延迟了残余应变的恢复时间。

Mechanical responses of asphalt pavement under half-sine load

This paper studied the characteristics of tire/pavement contact mark and random load, established a three-dimensional finite element model of pavement structure by means of ABAQUS software and analyzed the mechanical responses of the asphalt pavement under half-sine load. The results show that stress and strain are concentrated in the top and middle layers of pavement structure under half-sine load and their values decrease with the increase of the pavement depth. Maximums of vertical, transverse and longitudinal stresses appear in the top layer of pavement structure, and vertical stress is the largest, followed by transverse then longitudinal stresses. Maximal vertical and transverse strains also appear in the top layer, but maximal longitudinal strain is in the top-middle layer and repeated tension-compression deformation in the longitudinal direction exists in the pavement structure which is likely the fundamental cause of material fatigue damage near the wheel path of asphalt pavements. In addition, load duration and pavement temperature have greater influences on the strain of asphalt pavement than on the stress. The rise of pavement temperature leads to the increase of strain and delays the recovery of residual strain.