高速铁路无砟轨道软岩路堑基床换填厚度研究

Research on Replacement Thickness of Soft Rock Cutting Subgrade Bed of High-speed Railway with Ballastless Track

针对高速铁路无砟轨道在软岩地区基床承载能力不足的问题,本文通过调研无砟轨道路基荷载的分布模式,确定了无砟轨道路基面动荷载分析简化模型。提出以路基基床的结构动强度、长期稳定性及循环变形为控制条件,探讨高速铁路无砟轨道软岩路堑基床长期动力稳定状态下的合理换填厚度。通过具体的计算示例说明了该方法的应用步骤,并研究了不同的无砟轨道结构形式对换填厚度的影响,最终给出了最小换填厚度建议值表格以便工程查用。

In view of the deficiency in the bearing capacity of subgrade bed of high-speed railway with ballastless track in soft rock area,a simplified model for dynamic load analysis of ballastless track subgrade surface is established by investigating the distribution mode of ballastless track subgrade load. Taking the dynamic structure strength,long-term stability and cyclic deformation of subgrade bed as control conditions,the reasonable replacement thickness of soft rock cutting subgrade bed of high-speed railway with ballastless track under long-term dynamic stability is discussed. The application steps of this method are illustrated by calculation examples,and the influence of different ballastless track structure forms on replacement thickness is studied. Finally,a recommended minimum replacement thickness table is given for engineering reference.