重载铁路路基动力响应的数值分析

通过大型有限元软件ANSYS，建立轨道-路基三维有限元模型，分析路基动应力沿线路横向和纵向的分布规律，以及不同轴重和基床表层模量对路基动应力的影响，为以后重载铁路基床的设计和养护维修提供参考。研究结果表明:路基面竖向动应力沿线路横向和纵向的分布都不均匀，横向大致呈“M”形。基床表层动应力的衰减最为急剧，约为40%。随着轴重的增加，路基各层竖向动应力都在增加。基床表层弹性模量为150 MPa时，轴重每增加5 t，基床表面竖向动应力最大增加26.1%。40 t轴载下，基床表层弹性模量每增加50 MPa，基床表面竖向动应力最大增加2.68%。

Numerical Analysis on Dynamic Response of Heavy Haul Railway Subgrade

This paper, with finite element software ANSYS, established a track-subgrade dimensional finite element model to analyze the horizontal and vertical distribution rule of subgrade dynamic stress along the line and the effect of both the axle load and the modulus of surface layer of subgrade bed on this stress, which provided a reference for subgrade design and maintenance of heavy haul railway. The research result shows that: on the subgrade surface, the vertical dynamic stress manifests an uneven distribution at the horizontal and vertical direction with a rough "M" shape crosswide; in the surface layer of subgrade bed, the dynamic stress manifests a most dramatic decay by about 40%; as the axle load increases, the vertical dynamic stress at each layer of subgrade increases; when the elastic modulus of the surface layer is 150 MPa, the vertical dynamic stress at the bed surface increases up to 26.1% at every 5 t increment on the axle load; under 40 t axle load, the vertical dynamic stress at the bed surface increases up to 2.68% at every 50 MPa increment on the elastic modulus of the surface layer.