盾构机穿越地下连续墙引起既有车站振动的实测与分析

Measurement and Analysis of Vibration of Existing Station Caused by Shield Tunnel Crossing Underground Diaphragm Wall

为探明盾构机穿越既有车站地下连续墙诱发的车站结构振动响应规律,通过现场实测的方法,监测盾构刀盘切削地连墙过程中引起的振动,并对振动影响进行评价。研究结果表明,停机状态下,背景振动的主频为30.8 Hz,磨墙过程中,刀盘产生振动主频为89.3 Hz,相比于背景振动,磨墙产生的振动加速度峰值和有效值至少增加一个数量级;振动波传递至车站显著衰减,加速度峰值最大衰减率能达到近98.35%;除了31.5 Hz,车站测点各频段的最大振级均小于规范控制值;盾构穿墙引起车站结构振动速度为1.3 mm/s,小于国内外规范给定的标准值。

To investigate the vibration response law of station structure vibration induced by shield machine passing through the underground diaphragm wall of the existing station,the vibration caused by the shield cutter head cutting the underground diaphragm wall was measured by the method of field measurement,and the impact of the vibration was evaluated.The research results showed that the main frequency of the background vibration was 30.8 Hz in the stop state,and the main frequency of the vibration generated by the cutter head was 89.3 Hz in the process of cutting the wall.Compared with the background vibration,the peak value and effective value of the vibration acceleration generated by the cutting wall increased at least one order of magnitude.The vibration wave transmitted to the station was significantly attenuated,and the maximum attenuation rate of the acceleration peak value can reach nearly 98.35%.Except for 31.5 Hz,the maximum vibration level of each frequency band of the station measurement point were all smaller than the standard control value.When the shield tunneling through the underground diaphragm wall,the maximum response value of the vibration speed was 1.3 mm/s,which was less than the standard value given by domestic and foreign specifications.