高速重载有砟轨道路基动变形特性的数值分析

Numerical Analysis for the Dynamic Deformation Characteristics of the Ballast Subgrade on High-Speed and Heavy Haul Railway

运用ABAQUS有限元软件建立有砟轨道—路基系统三维动态有限元模型,分析高速和重载列车荷载作用下的路基空间动应力、路基面横纵向动变形和剪应变特性。基于现场条件,选择砟脚内30cm和砟脚处作为路肩横向和纵向的动变形分析参考点,研究动变形引起的路肩倾斜角度随列车速度、道砟厚度、表层厚度和表层模量变化的规律。结果表明,路肩横向和纵向倾斜角随车速增大而增大,随道砟厚度、基床表层厚度和表层模量的增大而减小,基床表层和底层的最大剪应变较为接近,最大剪应变与路肩最大倾角大致呈线性关系。

With ABAQUS FE software, 3D FE dynamic models of the ballast track-subgrade system were developed to analyze the spatial dynamic stress of the subgrade, the lateral and longitudinal dynamic deformation of the subgrade surface and the shear strain under the loads of high-speed and heavy haul trains. Based on field condition, the reference points for analyzing the lateral and longitudinal dynamic deformation of the road shoulder were chosen at 30 cm inward from the ballast slope angle and at the ballast slope angle, respectively. The change law of the road shoulder inclination, which resulted from the dynamic deformation, along with the train speed, ballast thickness, surface bedding thickness and the modulus of bedding surface was studied. The results show that the lateral and longitudinal inclination angles increase with the increase of the train speed while decrease with the increase of the ballast thickness, the thickness and the modulus of the bedding surface. The maximal shear strain of the bedding surface is close to that of the bedding bottom, and the linear relationship between the maximal shear strain and maximal slope angle of the road shoulder is obtained.