沥青路面非线性疲劳损伤特性及应力状态演变规律

Nonlinear fatigue damage characteristics and stress evolution law of asphalt pavement

运用通用有限元软件ABAQUS及其二次开发平台,建立考虑路面材料非线性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的空间分布、演化规律以及路面结构内部水平正应力的空间分布与演化规律。研究结果表明:路面结构损伤主要分布在双轮中心线下靠近基层与底基层层底的区域,随着荷载作用次数增加,基层层底与底基层层底损伤度均增加,且增加幅度逐渐增大;双轮中心线下靠近基层与底基层层底区域,考虑损伤的路面结构相比无损路面结构,层底水平拉应力均有所减小,且随荷载作用次数增加,水平拉应力逐渐减小,减小的幅度逐渐增大。研究结果可用于路面维修养护中路面破坏区域及程度的判断,以及路面设计研究中设计指标的确定。

Using general finite element software ABAQUS and the secondary development platform, an asphalt pavement numerical model which considers the pavement material nonlinear fatigue damage was established to analyze the asphalt pavement structure damage＇s spatial distribution and evolution, the spatial distribution and evolution of the horizontal stress within the pavement structure. The results show that the pavement structural damage mainly distributes in a specific damage zone located at the bottom of the base and sub-base 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 and the sub-base increases, and the rate of which gradually increases. The horizontal tensile stress in the specific damage zone of a pavement structure considering damage is less than that of the pavement structure without considering damage. Simultaneously, this horizontal tensile stress gradually decreases, and the rate increases with the increase of load cycles. The results can be used to judge failure region and degree of the pavement structure on the asphalt pavement maintenance, and to determine the design index of the asphalt pavement design research.