考虑空间参数随机特征的沥青路面力学行为分析

Analysis of Mechanical Behavior of Asphalt Pavement Considering the Random Characteristics of Spatial Parameters

沥青路面作为应用广泛的路面结构在我国设计规范中被视为各向同性弹性多层体系,这种假设使得设计过程中无法准确描述沥青路面实际工作状态下的受力情况。本文运用平稳随机场参数模型来描述沥青混合料的各向异性,再通过有限元模型模拟沥青路面结构的受力状况,进行确定性和随机性的分析和评价。研究得出:运用随机场理论并采用平稳随机场参数模型分析沥青混合料的各向异性是可行的,对面层层底应力影响较小,对层底应变及层顶竖向位移有一定影响,如果只考虑各向同性将会高估路面结构的稳定性,因此沥青路面设计应考虑沥青混合料的各向异性。

As a widely used pavement structure, asphalt pavement is considered as an isotropic elastic multi-layer system in the Chinese specifications for the design of asphalt pavement. This assumption makes it impossible to accurately describe the stress and strain of the asphalt pavement under the actual working state in the design process. In this paper, a stable random field parameter model has been used to describe the anisotropy of the asphalt mixture, while the finite element model was used to simulate the mechanical behavior of the asphalt pavement structure to perform deterministic and random analysis and evaluation. The results show that it is feasible to analyze the anisotropy of asphalt mixture using random field theory and a stable random field parameter model. And the anisotropy of the asphalt layer has little effect on the stress at the bottom of the surface layer, a certain effect on the strain at the bottom and vertical displacement of the top layer. If only considering isotropy, the stability of the pavement structure will be overestimated. Therefore, the anisotropy of asphalt mixture should be considered in asphalt pavement design.