高速铁路路基基床结构分析及设计方法

Structural Analysis and Design Method for Subgrade Bed of High-speed Railway

基于实测资料,分析路基动荷载、动应力和动变形的特点。按照分担比,将列车荷载分配到轨枕上,再利用Boussinesq弹性理论公式和Odemark的模量与层厚当量假定进行设计计算。当计算选取的介质模量值考虑应变水平影响时,计算与实测结果有较好的一致性,从而建立一种路基基床的分析计算模式。结合临界体积效应应变的概念,以控制重复荷载作用下路基不发生累积变形和累积孔压等累积效应为目的,提出路基基床结构的应变控制设计方法。

Based on field test data, the dynamic load, stress and deformation characteristics of subgrade are analyzed. Train load is distributed to sleepers in proportion. The dynamic load, stress and deformation of subgrade are calculated by adopting the method of Boussinesq elasticity theory formula and with Odemark equivalent hypothesis of modulus-thickness. When the value of modulus in calculation is decided by standard of strain, the result of calculating is consistent with the test. Thus a method of calculating for subgrade is proposed. With volumetric cyclic threshold shear strain, a design method of subgrade on control strain is advanced. The idea is to control accumulative effect such as accumulative deformation and pore water pressure of subgrade.