移动荷载作用下长大纵坡沥青路面力学响应分析

Research on Mechanical Response of Asphalt Pavement with Moving Load on Long and Steep Longitudinal Slope

为了研究结构层参数对长大纵坡沥青路面结构力学性能和路用性能的影响作用，采用有限元软件建立了移动荷载模型及长大纵坡沥青路面结构三维有限冗模型，分析了移动荷载作用下，面层、基层竖向压应力、最大剪应力、层底拉应力随各结构层厚度、模量及结构层组合的变化规律。结果表明：面层模量的增加在提高路面抗车辙性能的同时会降低其抗疲劳开裂性能；增大基层模量可以提高面层抗疲劳性能，但同时增加了基层层底拉应力，降低了基层抗疲劳性能；对于刚度较大的半刚性基层，面层厚度取低值可以增强长大纵坡沥青路面的抗车辙性能，基层厚度对于路面结构抗车辙性能影响较小；面层与基层模量比值在0．8～1．1范围内变化时，对长大纵坡沥青路面结构受力较为有利。

In order to study the Influence of asphalt pavement mechanical property and performance by parameters of structural layer, a mobile load model and three-dimensional finite element model of asphalt pavement on Long and Steep Longitudinal Slope were established by finite element software , then, the Variation of vertical compressive stress, maximum shear stress, tensile stress of surface course and base course with moving loads were analyzed when the layer thickness, modulus and structural layer combinations changed. The results show that, anti-rutting performance will be enhanced by increasing surface modulus of surface course ,but the anti-fatigue cracking performance will be reduced ; increasing the modulus of base course can enhance the anti-fatigue properties of the surface layer, but it increases the tensile stress at the end of the base course ,reduce its anti-fatigue performance; For the semi-rigid base with larger stiffness, the anti-rutting performance of asphalt pavement surface layer can be increased by reducing the thickness of surface course, the impact on anti-rutting performance of pavement is less from the thickness of base course thickness; it is beneficial for asphalt pavement structure that the values of modulus ratio of surface course and base course change from 0.8 to 1.1.