天津软土地区地铁运营沿线地面振动响应实测与建模分析

首先利用CMG-5TCDE一体化强震仪,对天津地铁5号线职业大学站-淮河道站区间沿线进行场地地表振动强度测试;接下来基于实际工程数据,利用ABAQUS建立轨道-道床-隧道-土层三维有限元模型,数值模型通过Py-thon程序实现黏弹性边界的设置,并应用DLOAD子程序实现列车轮载的移动施加,最终采用动力隐式分析方法模拟计...

Field Test and Finite Element Modeling of Ground Surface Vibration Caused by Metro Line Operation

A test is carried out to study the ground surface vibration intensity along the Tianjin Metro Line 5 by using the instrument of CMG-5CTDE.Based on actual engineering data,a three-dimensional finite element model of tunnel-soil layer is established by using ABAQUS code.The model’s viscoelastic boundary is determined by Python programming,and the moving load of the train is simulated by using DLOAD subroutine.Finally,the dynamic implicit analysis method is used to calculate the vibration response of the ground surface during the train passing the underground.The results show that there is a significant difference between the ground vibration intensities when the train travels in and out of the tunnel,and the vibration intensities at the measurement points increase significantly when the train passes through the tunnel.At the same time,the vertical vibration of the ground caused by the metro operation decreases significantly with the distance from the tunnel increasing.This study indirectly verifies that the three-dimensional finite element method has a high accuracy in simulating the influence of subway train on ground vibration:in terms of vibration intensity,the difference between simulation and measured values of Z vibration level of ground surface is less than 2 dB;in terms of the peak value of vertical vibration acceleration,the difference between finite element simulation and measured values is less than 5.0×10^4 m/s^,and the prediction error rate is within 4.5%-7%.