富水砂层大直径深竖井开挖稳定性有限元分析  

Finite Element Analysis of Excavation Stability of Large-diameter Deep Shaft in the Water-Rich Sand Layer

作　　者：周巾森 肖明砾[1,2] 谢红强[1,2] 何江达[1,2] 裴建良[1,2] ZHOU Jinsen;XIAO Mingli;XIE Hongqiang;HE Jiangda;PEI Jianliang(State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu Sichuan 610065;College of Water Resource and Hydropower,Sichuan University,Chengdu Sichuan 610015)

机构地区：[1]四川大学水力学与山区河流开发保护国家重点实验室,四川成都610065 [2]四川大学水利水电学院,四川成都610065

出　　处：《四川水力发电》2024年第1期116-122,共7页Sichuan Hydropower

摘　　要：某输水隧洞盾构接收竖井具有开挖直径大、深度深、砂层水位高的特点,对开挖过程中竖井结构受力和变形提出更高的要求。笔者以该竖井工程为研究对象,采用有限元分析方法模拟了竖井的施工过程,研究了竖井地下连续墙及地层在开挖过程中的位移、应力规律。分析结果表明:竖井开挖完成后,地表最大隆起为39.50 mm,出现在井口附近;地层最大隆起为41.60 mm,出现在井底地层。地下连续墙最大水平位移为2.79 mm,出现在竖井顶部,地下连续墙顶部水平位移计算值与实测值吻合较好。地下连续墙最大拉应力为1.13 MPa,未超过混凝土标准抗拉强度,表明盾构接收竖井开挖稳定性良好。笔者分析方法及结果可供类似工程参考。A shield receiving shaft of a water conveyance tunnel has the characteristics of large excavation diameter,depth and high water level in sand layer,which puts forward higher requirements for the stress and deformation of the shaft structure during the excavation.In this paper,the construction process of this shaft is simulated by finite element analysis and the displacement and stress laws of underground diaphragm wall and the stratum of the shaft during the excavation process are studied.The analysis results show that after the shaft excavation is completed,the maximum surface uplift is 39.50 mm,which appears near the wellhead;the maximum stratigraphic uplift is 41.60 mm,which appears in the bottom hole formation;the maximum horizontal displacement of the underground diaphragm wall is 2.79 mm,which appears at the top of the shaft.The calculated value of the horizontal displacement at the top of the underground diaphragm wall is in good agreement with the measured value.The maximum tensile stress of the underground diaphragm wall is 1.13 MPa,which doesn't exceed the standard tensile strength of the concrete,indicating that the excavation stability of the shield receiving shaft is good.The analysis method and results in this paper can be used as reference for similar projects.

关 键 词：富水砂层 竖井开挖 地下连续墙 数值模拟 

分 类 号：TV314[水利工程—水工结构工程] TV331