流-固耦合作用下深基坑施工对地铁盾构隧道的影响

Influences of Excavation of Deep Foundation Pit on Metro Tunnels under Fluid Structure Coupling

随着城市高速发展,越来越多的深基坑工程施工紧邻运营地铁盾构隧道,对其安全运营产生了非常大的影响。依托昆明市某地铁盾构隧道附近的深基坑开挖项目,采用有限元数值分析方法,研究流-固耦合作用下深基坑开挖对邻近地铁盾构隧道的影响。研究结果表明:(1)依托项目按照设计要求考虑时空效应,采用分期分块进行施工,对运营中的地铁盾构隧道的结构安全不会造成影响;(2)深基坑开挖不考虑渗流场作用时,以影响地铁盾构隧道水平变形主,深基坑开挖考虑渗流场作用时,以影响地铁盾构隧道竖向变形主;(3)流-固耦合作用下,深基坑开挖后地面沉降线由原来的抛物线变为倒驼峰形状。

With the rapid development of the city, that more and more deep foundation pit projects are constructed close to the shield tunnel has a great impact on the operating subway section. In this paper, based on the example of a deep foundation pit excavation project near a shield tunnel in Kunming City, the finite element numerical analysis method is used to study the influence of deep foundation pit excavation on the adjacent shield tunnel under fluid solid coupling. The research shows that construction by stages and blocks will not affect the structural safety of the subway interval shield tunnel according to the design requirements and considering time and space effect;Not considering the effect of seepage field in deep foundation pit excavation, the horizontal deformation of shield tunnel will be affected. Considering, the vertical deformation of shield tunnel will be affected;Under fluid solid coupling, the ground settlement line after the excavation of the foundation pit changes from the original parabola to the inverted hump shape.