沥青路面线性疲劳损伤特性及应力状态演变规律

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及应力状态演变规律,运用通用有限元软件ABAQUS及二次开发平台,建立考虑路面材料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以及路面结构内部水平正应力的空间分布与演化规律。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,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,但增加幅度逐渐减小;双轮中心线下靠近层底区域,考虑损伤的路面结构相比无损路面结构,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,但减小的幅度逐渐趋缓。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。

Linear Fatigue Damage Characteristics and Stress Evolution Regularity of Asphalt Pavement

In order to study the fatigue damage characteristics and stress evolution regularity of asphalt pavement under vehicle load,by using general finite element software ABAQUS and the secondary development platform,a numerical model of asphalt pavement considering pavement material linear fatigue damage was established to analyze the spatial distribution and evolution of asphalt pavement structure damage under repeat vehicle loads,and to analyze the horizontal normal stress within the pavement structure.The results show that(1) The pavement structural damage mainly distributes in a specific damage zone located near the bottom of the layer along the middle line between the double wheels.With an increasing of the load cycles,the damage degree at the bottom of the base layer and the sub-base layer increases,but the rate of which gradually decreases.(2) 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 of which also decreases with the increase of load cycles.The results can be used to judge the failure region and degree of the asphalt pavement under maintenance,and to determine the design index of the asphalt pavement design research.