基坑开挖对邻近地铁隧道的影响研究

Study on the Influence of Foundation Pit Excavation on Adjacent Subway Tunnel

随着城市建设的发展,城市轨道交通网络逐渐完善,地铁隧道在其正常运营阶段不可避免地要受到各种新建工程活动的影响,其中包括基坑工程。文中以上海地铁二号线南侧越洋广场项目基坑工程为背景,采用三维快速拉格朗日法,对基坑开挖过程进行数值模拟,结果表明,在基坑开挖过程中,基坑周围土体变形以竖向位移为主,地铁隧道的变形以水平位移为主。同时,对基坑底部土体进行预加固措施,可明显减小基坑开挖对地铁隧道的影响。

With the development of urban construction,urban transit network has been gradually improved,but subway tunnel under its normal operation is inevitably affected by various new engineering activities such as foundation pit engineering.Based on foundation pit engineering of Oversea Square at southern side of Shanghai Subway No.2 Line,this paper carries out numerical simulation on foundation pit excavation process using 3D rapid Lagrange method.The result shows that during foundation pit excavation,the surrounding soil mass deformation is mainly of vertical displacement and subway tunnel deformation is mainly of horizontal displacement.Meanwhile,pre-reinforcement on bottom soil mass can significantly reduces the influence of foundation pit excavation on subway tunnel.