交叠隧道引起地表及既有隧道变形规律分析  

Analysis of deformation patterns of ground surface and existing tunnels caused by overlapping tunnels

作　　者：肜增湘 余炳臻 戴灏卿 李旋 罗学东[2] 付超 RONG Zengxiang;YU Bingzhen;DAI Haoqing;LI Xuan;LUO Xuedong;FU Chao(Hubei Communications Planning and Design Institute Co.,Ltd..,Wuhan 430051,China;Faulty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China;Wuhan Municipal Construction Group Co.,Ltd.,Wuhan 430023,China)

机构地区：[1]湖北省交通规划设计院股份有限公司,湖北武汉430051 [2]中国地质大学(武汉)工程学院,湖北武汉430074 [3]武汉市市政建设集团有限公司,湖北武汉430023

出　　处：《安全与环境工程》2024年第4期58-67,共10页Safety and Environmental Engineering

基　　金：国家自然科学基金项目(42072309)。

摘　　要：为了研究新建盾构隧道上穿既有隧道引起的地表沉降和隧道变形规律,以武汉轨道交通5号线一期工程施工为背景,利用FLAC3D软件进行了数值模拟,分析了新建左线隧道上跨施工对下卧左线和上跨右线隧道及地表土体变形的影响,并与现场实测结果进行了对比分析。结果表明:新建盾构隧道上穿对既有隧道水平变形的影响较小,需重点关注既有隧道竖向变形和盾构区变形监控工作;随着新建隧道掌子面推进,既有隧道距离掌子面越近处变形速率越大;开挖引起的隧道外地表沉降符合正常开挖沉降规律,即离隧道中心点越近,地表沉降量越大,开挖至中部时地表变形速率较快,接近稳定阶段开挖时地表变形速率较慢;交叠段开挖完成后地表沉降数值模拟结果与实际盾构施工现场地表监测数据之间的误差最大仅为4.32 mm,在误差允许范围内。研究结果对同类工程应用具有一定的指导价值,能为类似工况下的工程施工提供参考。To study the surface settlement and tunnel deformation caused by the new shield tunnel passing through the existing tunnel,the construction of Wuhan Metro Line 5 Phase I project was taken as the background.The FLAC~(3D)software was used for numerical simulation to analyze the influence of the construction of the new left-line tunnel on the deformation of the underlying left-line and the overpass right-line tunnels and the surface soil,and the results were compared with the field measurement results.The results show that the new overpass tunnel has little effect on the horizontal deformation of the existing tunnel,and it is necessary to focus on the vertical deformation of the existing tunnel and the deformation monitoring of the shield area;as the new tunnel face advances,the deformation rate of the existing tunnel increases as it is closer to the face;the surface settlement outside the tunnel caused by excavation conforms to the normal excavation settlement law,i.e.,the closer to the center of the tunnel,the greater the surface settlement,the faster the surface deformation rate is when excavating is close to the middle,and the slower the deformation rate is when excavating is close to the stable stage;finally,compared with the actual project,it is found that the maximum error between the numerical simulation results of the surface settlement after the overlapping section excavation is completed and the surface monitoring data of the actual shield construction site is only 4.32 mm,which is within the error range.The research results have certain guiding value for engineering applications and can provide reference for projects under similar working conditions.

关 键 词：盾构上穿隧道 变形特征 地表沉降 数值模拟 现场监测 

分 类 号：X948[环境科学与工程—安全科学]