长大纵坡沥青路面有限元分析

针对长大纵坡上坡路段沥青路面易产生车辙破坏的现象, 以粘弹性沥青混合料本构模型为基础, 选取了5种不同的纵向坡度, 采用ABAQUS有限元软件分析了标准轴载作用下沥青混合料面层内最大剪应力和竖向应变的分布规律, 并对有坡和无坡状态下荷载与车速的影响进行了分析。计算结果表明: 最大剪应力和竖向应变随坡度和荷载的增大而增大, 随车速的增大而减小, 且有坡路段受荷载和车速的影响更大; 位于路表下4~10 cm深度处中面层的最大剪应力和竖向应变平均值都大于其他结构层, 是最容易产生车辙的结构层位, 因此, 提高长大纵坡路段沥青路面中面层的抗车辙性能尤为重要。

Finite element analysis of asphalt pavement on long-steep longitudinal slope

Because the rutting damages of asphalt pavement easily appeared at uphill sections of long-steep longitudinal slope, five different slopes were chosen based on the visco-elastic constitutive model of asphalt mixture, and the distribution regularities of the maximum shear stress and vertical strain for mixture surface course under the action of standard axle load were analyzed by finite element software ABAQUS. The impacts of traffic load and vehicle speed on road sections with and without slopes were also presented. Calculation result indicates that maximum shear stress and vertical strain are directly proportional to slope and traffic load and inversely proportional to speed. Road sections with slopes are more sensitive to traffic load and speed. The average values of the maximum shear stress and vertical strain in the middle layer, which ranges from 4~10 cm below road surface, are greater than that of other layers. So the rutting damages are most likely to appear in the middle layer, and it is more important to improve the rutting resistance of middle layer for long-steep longitudinal slope.