基坑施工引起临近地铁隧道变形实测及有限元分析  

Deformation Measurement and Finite Element Analysis of Subway Tunnel Deformation Caused by Foundation Pit Construction

作　　者：孙斌彬 陈甦[1] 李学东 陈春明 唐强[1] Sun Binbin;Chen Su;Li Xuedong;Chen Chunming;Tang Qiang(School of Urban Rail Transportation, Soochow University, Suzhou 215137;The 4th Geological Brigade of Jiangsu Geology&Mineral Exploration Bureau, Suzhou 215129)

机构地区：[1]苏州大学城市轨道交通学院,江苏苏州215137 [2]江苏省地质矿产勘察局第四地质大队,江苏苏州215129

出　　处：《森林工程》2017年第5期96-103,共8页Forest Engineering

基　　金：江苏省地质矿产勘查局科研项目(2014-KY-7)

摘　　要：为了研究基坑施工对临近既有地铁隧道变形的影响,对苏州地区10个基坑施工引起的临近地铁隧道变形监测数据进行整理统计,分析隧道变形随基坑施工发展的时空特征。研究表明:基坑施工导致临近地铁隧道朝基坑方向移动,同时引起拱顶沉降、道床隆起以及隧道断面水平向拉伸;隧道水平位移、竖向位移以及水平收敛变形随基坑开挖深度的加大而增大,一般在基坑开挖完成或者支撑拆除时达到最大值;隧道变形曲线空间分布具有对应基坑中部或中部附近处隧道断面变形较大的特点;隧道变形曲线的时空特征,受土方开挖方式、坑内加固、地面超载、降水活动、基坑与隧道相对空间位置关系等因素影响。对某基坑施工引起的临近地铁隧道变形的有限元模拟计算表明,隧道变形随地连墙厚度减小、基坑与隧道间距减小而增大。In order to study the influence of foundation pit construction on the deformation of the existing subway tunnels,the deformation monitoring data of10foundation pit projects in Suzhou were collected and counted,and the temporal and spatial characteristics of tunnel deformation with the development of foundation pit construction was analyzed.The following conclusions were arrived.First,construction of the foundation pit caused the adjacent subway tunnels to move towards the foundation pit as well as the vault to sink,the road bed to uplift,and the tunnel cross-section to elongate horizontally.Second,the horizontal,vertical displacement and horizontal convergence deformation of subway tunnel increased with the depth of excavation,and the maximal deformation usually appeared at the stage when the excavation had been completed or when the shoring of trench had been removed.Third,the spatial distribution of subway tunnel deformation curves had the maximal deformation at the cross-section corresponding to the middle of foundation pit or the surrounding area.Finally,the temporal and spatial characteristics of the tunnel deformation curve was affected by factors such as excavation method,reinforcement means,surface overloading,precipitation activity,and relative space between the foundation pit and tunnel.The finite element simulation of the deformation of a subway tunnel caused by a foundation pit construction showed that the deformation of the tunnel increased when the diaphragm wall got thinner and the decrease of the spacing between the foundation pit and the tunnel.

关 键 词：基坑 地铁隧道 水平位移 竖向位移 收敛变形 时空特征 

分 类 号：U231.1[交通运输工程—道路与铁道工程]