基于减隔振措施的曲线段变速地铁列车振动影响研究

为探究运行变速的地铁列车通过减振段引起的环境振动影响，选取成都地铁4号线宽窄巷子—中医大省医院区间钢弹簧浮置板减振段，建立“列车-轨道板-地层”三维有限元模型，并现场测试地铁运行时区间隧道及地表的竖向振动与水平振动，研究减振措施下曲线段变速地铁列车振动特征。结果表明:变速运行列车引起的道床及边墙振动时程曲线呈现出前期增长慢，后期衰减快的特点；列车变速运行下的道床及边墙的振动加速度波形不具备半周期对称性；在曲线段隧道结构的水平振动不可忽略；振动由道床传递至边墙过程中呈跳跃式衰减，钢弹簧浮置板具有良好的减隔振效果；道床和边墙处振动加速度的主要频率范围为60~100 Hz，振动由隧道内传递至地表过程中高频段衰减较快，地表处振动加速度的主要频率范围为5~30 Hz。

Study on Vibration Impact of Variable-speed Subway Train in Curve Section Based on Vibration Isolation Measures

In order to explore the impact of environmental vibration when variable-speed subway train runs through vibration attenuation section, the damping section of steel spring floating slab from Kuanzhaixiangzi Alleys to Chengdu University of TCM & Sichuan Provincial People's Hospital of Chengdu Metro Line 4 was selected to establish a 3D finite element model of train-track slab-stratum and, with the vertical and horizontal vibration of the interval tunnel and earth surface during operation of subway tested on site, the vibration characteristics of variable-speed subway train in curve section under vibration isolation measures were thus studied. The result shows that, the vibration-time history curve of ballast bed and side wall caused by operation of variable-speed train presents slow increase in early stage and fast attenuation in late stage; and the vibration acceleration waveform thereof is not of half-periodic symmetry; in the curve section, the horizontal vibration of the tunnel structure can not be ignored; the vibration when transferring from ballast bed to side wall presents skipping attenuation, and the steel spring floating slab plays good role of vibration isolation and damping; the frequency of vibration acceleration at the ballast bed and side wall mainly ranges from 60 Hz to 100 Hz, and the vibration when transferring from tunnel to earth surface presents fast attenuation at its high band; the frequency of vibration acceleration at earth surface mainly ranges from 5 Hz to 30 Hz.