基于PLAXIS 3D技术的深基坑开挖对既有地铁结构影响分析

摘要

运用PLAXIS 3D 有限元分析软件,对邻近既有地铁结构的某工程基坑开挖过程进行了模拟,分析了在开挖过程中地连墙位移的变化规律及开挖对既有地铁结构变形的影响.结果表明:基坑开挖会引起基坑长边中间部位的坑外地表发生沉降; 基坑开挖至坑底后,围护结构的变形模式为"内凸型",最大水平变形发生在基坑长边中间部位的坑底附近.%The excavation process of foundation pit of a project adjacent to the existing subway structur was simulated using the finite element analysis software PLAXIS 3D and the change rule of the even wall displacement and the influence of excavation on the deformation of the existing subway structure was analyzed. The result showed that: the ground surface settlement outside the pit caused by the excavation of the foundation pit occurred in the middle part of the long side of foundation pit, the deformation mode of the enclosure structure is"inner convex type"after excavation of the foundation pit to the bottom of the pit. The maximum horizontal deformation occurred near the pit bottom in the middle part of the long side of the foundation pit.