沥青路面线性疲劳损伤特性及形变规律

为了研究沥青路面结构在车辆荷载作用下的疲劳损伤演化特性并分析其形变规律,运用通用有限元软件ABAQUS及其二次开发平台,建立考虑路面材料疲劳损伤的沥青路面结构数值计算模型,分析沥青路面结构在车辆荷载反复作用下路面结构损伤和水平正应变的空间分布与演化规律,以及路表弯沉随荷载作用的演变规律.结果表明:路面结构损伤主要分布在双轮中心线下靠近层底的区域,基层层底与底基层层底损伤度随荷载作用均增加,但增加幅度逐渐减小；路面结构层内水平正应变在荷载作用下,靠近层底位置拉应变逐渐增大,但增加幅度逐渐减小,中性轴上移；路表弯沉在荷载作用下逐渐增大,但增加幅度逐渐减小.研究结果可为沥青路面结构设计、养护维修及长期性能预测提供理论支撑.

Linear fatigue damage characteristics and deformation law of asphalt pavement

In order to study the fatigue damage characteristics and the deformation of the asphalt pavement under vehicle load,using the general finite element software ABAQUS and the secondary development platform,an asphalt pavement numerical model which considers the pavement material fatigue damage is established to analyze the spatial distribution and evolution of asphalt pavement structure damage and horizontal normal strain,as well as the evolution law of the deflection on the surface of the pavement.The results show that the pavement structural damage mainly distributes in a specific damage zone that is located at the bottom of the layer and along the middle line between the double wheels.With the increase of the load cycles,the damage degree at the bottom of the base layer and the sub-base layer increases,the rate of which gradually decreases.Meanwhile,the horizontal tensile strain close to the bottom of the pavement layer increases,the rate of which gradually decreases,and neutral axis moves upward.The deflection on the surface of the pavement increases with the increase of load cycles,the rate of which decreases gradually.The results can provide a theoretical support for the asphalt pavement structure design,the maintenance and the prediction of the long-term performance.