摘要
为研究小净距隧道群在不同围岩条件下的TBM开挖稳定性,依托布吉南环路隧道工程,采用有限元软件Midas建立三维数值模型,对四导洞TBM开挖过程进行模拟。通过分析不同围岩等级下TBM掘进相互影响,系统揭示了隧道导洞开挖各阶段变形特征,并对模拟结果开展现场验证。研究结果表明:1)单导洞开挖时,拱顶沉降与地表沉降随开挖进尺呈非线性增长趋势,最终趋于稳定状态,且隧道收敛变形与开挖进尺呈显著正相关;2)多导洞群开挖过程中,后续导洞施工将引发已贯通导洞产生叠加效应,具体表现为拱顶沉降、水平位移及地表沉降量呈非线性累积增长,而水平收敛值呈非线性衰减特征,其中V级围岩区段叠加效应最为显著,导洞完全贯通时沉降量达到峰值。基于研究结果优化施工方案,通过全过程动态调控开挖支护参数,最终将隧道变形控制在允许范围内,有效保障了施工安全。
In order to study the TBM excavation stability of the tunnel group with small clear distance under different surrounding rock conditions,relying on the Buji South Ring Road tunnel project,the finite element software Midas is used to establish a three-dimensional numerical model to simulate the TBM excavation process of the four pilot tunnels.By analyzing the mutual influence of TBM tunneling under different surrounding rock grades,the deformation characteristics of each stage of the tunnel pilot tunnel excavation were systematically revealed,and on-site verification is carried out for the simulation results.The research results show that:1)When a single pilot tunnel is excavated,the vault settlement and the ground surface settlement show a non-linear growth trend with the excavation footage and finally tend to a stable state,and there is a significant positive correlation between the tunnel convergence deformation and the excavation footage;2)During the excavation process of the multi-pilot tunnel group,the construction of subsequent pilot tunnels will trigger a superposition effect on the already penetrated pilot tunnels.The specific manifestations are as follows:the vault settlement,horizontal displacement and ground surface settlement show a non-linear cumulative growth,while the horizontal convergence value shows a non-linear decay characteristic.Among them,the superposition effect in the section of Grade V surrounding rock is the most significant,and the settlement reaches its peak value when the pilot tunnel is completely penetrated.Based on the research results,the construction plan was optimized.By dynamically regulating the excavation and support parameters throughout the whole process,the tunnel deformation was finally controlled within the allowable range,effectively ensuring the construction safety.
作者
杨建
伏志威
俞杨
李恒光
陈保国
YANG Jian;FU Zhiwei;YU Yang;LI Hengguang;CHEN Baoguo(China Water Resources and Hydropower Seventh Engineering BureauCo.,Ltd.,Chengdu 610081,Sichuan,China;Jiangsu Liheng Engineering Consulting Co.,Ltd.,Nanjing 210001,Jiangsu,China;Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,Hubei,China)
出处
《工程建设》
2025年第8期55-63,共9页
Engineering Construction
关键词
隧道
围岩等级
小净距
TBM
地表沉降
围岩变形
tunnel
surrounding rock
small clear distance
tbm
ground surface settlement
deformation of surrounding rock
作者简介
杨建(1976-),男,高级工程师,从事市政工程施工技术研究与管理工作。
