重载铁路有砟-无砟轨道过渡段动力学特性

Dynamic Characteristics of Ballast⁃Ballastless Track Transition Section of Heavy Haul Railway

重载铁路不同形式的轨道连接处过渡段因刚度突变,易导致线路病害。建立重载铁路有砟-无砟轨道过渡段有限元模型,研究了过渡段位置、过渡段刚度分级以及支承层延伸长度对重载铁路有砟-无砟轨道过渡段动力学响应的影响。研究结果表明:为减小重载铁路过渡段荷载冲击效应对下部基础的影响,宜将有砟-无砟轨道过渡段设置在路基上;从减小过渡段轮轨冲击、延长轨道结构使用寿命以及减少过渡段病害产生的角度分析,过渡段应设置轨道结构分级过渡,同时设置支承层,支承层延伸至有砟轨道长度应在10 m左右,超过10 m后作用不明显。

Due to the sudden change of stiffness,the different forms of track joints transition section of heavy haul railway are easy to cause defects.A finite element model of ballast-ballastless track transition section of heavy haul railway was established,and the influences of transition section location,transition section stiffness classification and the length of supporting layer extending to ballast section on dynamic response of ballast-ballastless track transition section of heavy haul railway were studied.The research results show that in order to reduce the effect of load impact on the lower foundation of the transition section of heavy haul railway,the ballast-ballastless track transition section should be set on the subgrade.From the point of view of reducing the impact of wheel rail in the transition section,extending the service life of track structure and reducing the occurrence of defects in the transition section,the transition section should be set with graded transition of track structure.In addition,the supporting layer should be installed,and the length of the supporting layer extending to ballast track should be about 10 m,there are not significantly improvement whiler more than 10 m.