地铁列车引起的低频地表响应及减振措施研究

以北京某地铁标段减振措施研究为背景，研究地铁运营期间，列车振动荷载产生的低频地表响应的传播衰减规律及相应减振措施的效果，采用、Ansys软件进行有限元建模，利用改进的Newmark隐式时间积分法，针对5种减振工况，进行动力响应求解分析表明，与常规浮置板相比，新型的铜弹簧浮置板轨道结构对4Hz以上的低频振动在50m以内有明显减振效果．但50m以外效果不明显，且单纯加重浮置板重量对低频减振贡献不显著；同时辅助施作衬砌间的橡胶板垫层低频减振效果不明显.

A Study on the Low Frequency Ground Response Induced by Metro Train and Corresponding Vibration Reduction Measures

Based on the research of vibration reduction measures applied in Beijing metro, the paper focuses on the low - frequency ground motion induced by dynamic train bad during the running of metro. In order to show the law of waves propagation and effect of various vibration reduction measures, the FEM models for 5 cases of vibration reduction are set up and their dynamic responses are calculated by using ANSYS and the modified Newmark implicit time integration method. Following conclusions are arrived at: compared with conventional floating slab, the new steel spring floating slab track structure performs well within fifty meters for the excitation above 4HZ, while the effect is not so distinct beyond fifty meters; it contributes little to low-frequency vibration reduction by adding the weight of floating slab only; the assistant rubber layer also contributes little to low-frequency vibration reduction.