地铁运行引起地面局部振动放大现象的数值分析  

Numerical Analysis of Ground Vibration Amplification Phenomenon Caused by Subway Operation

作　　者：张啟乐 刘林芽[1] 李纪阳[1] 

机构地区：[1]华东交通大学铁路环境振动与噪声教育部工程研究中心,南昌330013

出　　处：《噪声与振动控制》2015年第2期116-120,共5页Noise and Vibration Control

基　　金：列车低噪声车轮声辐射优化模型及其遗传算法研究(51268014);江西省高等学校科技落地计划项目(2024)

摘　　要：以南昌地铁一号线穿越的土层为研究对象,建立轨道—隧道—大地的三维有限元模型,施加粘弹性人工边界,从隧道埋深,场地土层弹性模量等角度分析了由地铁运行所诱发的地面振动的传播规律。研究表明:地面振动的衰减并不是随着与隧道中心距离的增加呈严格意义单调递减,而是距离线路某一范围内存在一个振动放大区。隧道埋深越深,振动放大区出现在距离隧道越远的位置,而且振动放大区出现的次数会增加;土层越硬振动放大区越靠近隧道,振动放大区出现的次数会越多。振动放大区第一次出现在距离隧道约20 m^30 m处,振动反弹量比较大,被放大频率带主要分布在6 Hz^28 Hz,其中8 Hz^12 Hz最为集中,如果侵入建筑群,需特别关注。第二次第三次振动反弹量小,重视程度可以放宽。Taking the soil stratum of Nanchang No.1 subway as the research object, the rail-tunnel-soil coupled 3D finite element model was established, and the artificial cohesive elastic boundary condition was applied. The propagation law of ground vibration induced by the subway operation was analyzed in the aspects of the depth of the tunnel and the elastic modulus of the soil stratum. The research shows that the ground vibration does not attenuate monotonically with the increasing of the distance from the subway, but there exist several vibration amplification regions somewhere else. With the increasing of the depth of the tunnel, the amplification regions go farther away from the tunnel and their number increases. With the increasing of the elastic modulus of the soil stratum, the amplification regions go closer to the tunnel and their number also increases. The nearest vibration amplification region, referred to as the first amplification region, is about 20 m-30 m away from the tunnel, and the vibration bounce is large there. Amplification frequency bands are distributed in the 6 Hz- 28 Hz range, and mainly concentrated in 8 Hz-12 Hz. One should pay special attention to the first amplification region if it invades nearby building areas. However, the second and third amplification regions can be ignored since they have only small vibration bounces.

关 键 词：振动与波 地铁 有限元模型 振动放大区 隧道埋深 土层弹性模量 

分 类 号：TB533.2[理学—物理]