深基坑开挖对邻近隧道变形影响的数值模拟分析

针对上海某项目工程，运用MIDAS GTS有限元软件，分析了基坑开挖对侧向及底部近接隧道的位移影响规律。结果显示，基坑开挖主要造成侧向隧道发生水平位移，对竖向位移影响不大，且水平位移随着隧道与基坑间距的增大而减小，减小幅度逐渐变小。对底部隧道主要会引起竖向位移，水平位移可以忽略不计，竖向位移随着隧道与基坑间距的增大而减小，减小幅度呈增大趋势。此外，对基坑周围多管线存在情况进行了安全分区，通过分区对隧道管线进行安全评估，并提出相应的应对措施。

Numerical Simulation of Influence of Deep Foundation Pit Excavation on Adjacent Tunnel Deformation

GTS MIDAS finite element software was used herein in relation to a project in Shanghai to analyze the law how foundation pit excavation influences the displacement of adjacent tunnel at the side and the bottom. The result shows that, foundation pit excavation mainly causes horizontal displacement of lateral tunnel with minor effect on the vertical displacement, and the horizontal displacement decreases with the tapered decrement when the distance between the tunnel and the pit increases; for the bottom tunnel, the vertical displacement is caused mainly and the horizontal displacement may be neglected, and the vertical displacement decreases with the decrement presenting a uptrend when the distance between the tunnel and the pit increases. Moreover, for the situation of multiple lines existing around the foundation pit, the safety zoning was carried out with the security evaluation made therein, thus the related countermeasures were proposed.