双线地铁运营隔振沟屏障性能研究
Vibration Isolation Effect of Isolation Trenchesduring Double-Line Subway Operation

为研究双线地铁运营时隔振沟的减振效果，基于2.5维有限元法建立双线地铁列车-轨道-地基土体耦合分析模型。模型克服现有研究将轨道结构简化为弹性地基欧拉梁的缺陷，引入实际钢轨动力学参数，实现双线地铁列车荷载下隔振沟对周围地基的隔振效果分析，比较空沟、填充沟两种不同隔振措施的减振特性，并对填充沟隔振影响因素进行系统的参数分析。研究结果表明：双线运营地铁荷载下，空沟隔振作用体现在沟后范围内，填充沟减振范围更广且效果更好，相比空沟更具工程实用性；填充沟在沟深较小时也能发挥良好的减振作用，增大沟深、沟宽均可有效提高减振效果。研究成果可为今后双线地铁隔振设计与施工提供有益参考。
A coupled model of a double-line subway train-track-foundation soil was established on the basis of 2.5D FEM to study the vibration isolation effect of the isolation trench during double-line subway operation.The model addresses the problems introduced by the simplification of track structures into an Euler beam on an elastic foundation and introduces the dynamic parameters of the actual rail.The model was used to analyze the vibration isolation effect of the isolation trench on the surrounding foundation under double-line subway train load.The vibration damping characteristics of open and in-filled trenches were compared, and the trench factors that influence isolation were systematically analyzed.Results showed that under the double-line subway load, the in-filled trench had better isolation and engineering practicality than the open trench.The in-filled trench can exert a good damping effect even with a reduced ditch depth.In addition, the isolation effect can be improved by increasing the depth and width of the in-filled trench.The results of the present work can provide useful reference for the vibration isolation design and construction of double-line subways in the future