紧贴已建轨交车站的超深基坑开挖卸载效应数值模拟分析

Numerical Simulation Analysis of Unloading Effect of Extra-deep Excavation Close to Existing Rail Transit Station

结合上海某轨交建设工程实例,采用地层位移法,运用叠加原理和增量法,对紧贴既有轨交车站(地下连续墙共用)的深基坑开挖过程进行了二维和三维数值模拟。着重分析了深基坑开挖卸载作用下,既有车站结构的内力变化和变形趋势,对深基坑工程的施工提出了合理的控制要求。

Combined with an actual case of Shanghai rail transit engineering,2D and 3D numerical simulations are conducted to study the excavation process of extra-deep excavation pit which is close to a rail transit station( sharing a diaphgram wall) by ground displacement method,superposition principle and incremental method. Analysis is made to the internal force change and deformation trend of the existing station structure under the unloading effect of extra-deep excavation. And the rational control requirements are proposed for construction of deep excavation pit.