[关键词]
[摘要]
为研究车辆段不同轨道型式、不同基床结构下路基对列车的振动响应特性,依托郑州地铁铁炉西车辆段工程,开展不同路基结构条件下的动荷载数值模拟分析,研究路基动荷载分布随路基结构的变化规律。结果表明:无砟轨道在列车相同速度下产生的动荷载值小于有砟轨道。基床表层厚度增加对于列车行驶产生的动荷载减小效果更加明显。但是,过厚的基床会提高路基的刚度,不利于应力消散,因此基床厚度加到一定程度之后,减小动荷载产生的作用逐渐不明显。数值模拟结果表明:地铁车辆段路基设计方案可在“0.3+0.9”和“0.4+0.7”的基础上分区、合理制定,以基底动静应力比小于0.2为准,以期安全、经济、合理。
[Key word]
[Abstract]
The design standards for the roadbed structure of the metro depot have not been clearly defined in the "Metro Design Specification(2013)", and the current practice of using the main line standard results in high and unreasonable costs. This article relies on the Zhengzhou Metro Tieluxi Depot project to carry out numerical simulation analysis of dynamic loads under different subgrade structures, and studies the variation law of dynamic load distribution. The dynamic load generated by ballastless track at the same train speed is smaller than that of ballasted track. The increase in the thickness of the subgrade surface layer has a more significant effect on reducing the dynamic load generated by train operation. However, an excessively thick foundation will increase the stiffness of the roadbed, which is not conducive to stress dissipation. Therefore, when the foundation thickness is increased to a certain extent, the effect of reducing dynamic loads gradually becomes less significant. The numerical simulation results show that the design scheme of the metro depot subgrade can appropriately increase the parameters on the basis of "0.3+0.9" and "0.4+0.7", ensuring that the dynamic and static stress ratio of the subgrade is strictly less than 0.2, achieving the best level of safety and economy.
[中图分类号]
[基金项目]
国家自然科学(合同编号:71771020);