软土地层地铁隧道受两侧基坑群开挖叠加影响研究  

Superposed Effects on Deformation of Metro Tunnels in Soft Soils Caused by Excavation of Foundation Pits on Both Sides

作　　者：王卫东 徐中华 顾正瑞 宗露丹 WANG Weidong;XU Zhonghua;GU Zhengrui;ZONG Ludan(Arcplus Group PLC,Shanghai 200011,China;Shanghai Engineering Research Center of Safety Control for Facilities Adjacent to Deep Excavations,Shanghai 200011,China;Shanghai Underground Space Engineering Design&Research Institute,East China Architecture Design&Research Institute Co.,Ltd.,Shanghai 200011,China)

机构地区：[1]华东建筑集团股份有限公司,上海200011 [2]上海基坑工程环境安全控制工程技术研究中心,上海200011 [3]华东建筑设计研究院有限公司上海地下空间与工程设计研究院,上海200011

出　　处：《隧道建设(中英文)》2024年第S2期52-61,共10页Tunnel Construction

摘　　要：上海地铁12号线隧道横穿乍浦路天潼路基坑群工程,地铁隧道在两侧基坑群开挖的叠加影响下,变形性状更加复杂。采用分坑方案减小基坑的尺寸可以有效控制隧道变形,在基坑群复杂的工况下,不同分坑开挖对隧道的变形影响不同。基于可考虑土体小应变特性的HS-Small本构模型模拟分析地铁隧道在基坑群施工全过程的变形性状,进一步揭示基坑群分坑开挖引起邻近地铁隧道的渐次变形过程。结果表明:1)当隧道两侧都开挖时有利于水平变形的控制,而隧道的竖向位移由于两侧开挖的叠加影响表现为更大的沉降;2)隧道均发生竖向压缩和水平向拉伸变形,收敛变形不大,可保障隧道安全。The Shanghai metro line 12 crosses the Tiantong road and Zhapu road foundation pit groups.The deformation characteristics of the metro tunnels are complex due to the superposed effects caused by excavation of foundation pits on both sides of the tunnel.Sub-pit excavation method is adopted to reduce the excavation size of the foundation pit,thus the deformation of the tunnel can be effectively controlled.However,different sub-pit excavation schemes might cause different effects on the metro tunnels.Three-dimensional finite element analyses are carried out based on the small strain soil constitutive model and considering the interaction between soils and structures.Gradual deformation and superposed effects on the adjacent metro tunnels caused by excavation are revealed.It is beneficial to control the horizontal deformation of tunnels when synchronously excavating the foundation pits on both sides,but the vertical displacement of tunnel exhibits larger settlement due to superposed effect.In general,the excavation of the foundation pit causes both vertical compression and horizontal tensile deformation of the tunnels.However,the convergence deformation of the tunnel is not significant,showing that the tunnel is still in safe state.

关 键 词：基坑群 地铁隧道 叠加影响 变形性状 三维有限元 

分 类 号：U45[建筑科学—桥梁与隧道工程]