特大断面浅埋偏压隧道双侧壁工法工序优化分析  

Optimization Analysis of Double⁃side Wall Construction Method for Super⁃large Section Shallow⁃buried Bias Tunnel

作　　者：欧敏 李祥东 彭小丽[4] 蒋彪 张进华 OU Min;LI Xiangdong;PENG Xiaoli;JIANG Biao;ZHANG Jinhua(Hunan Provincial Communications Planning,Survery&Design Institute Co.,Ltd.,Changsha,Hunan 410200,China;Hunan Provincial Rail Survey&Design Institute Co.,Ltd.,Changsha,Hunan 410200,China;Qingdao Metro Group,Qingdao,Shandong 266000,China;Jiangxi College of Applied Technology,Ganzhou,Jiangxi 341000,China;Hunan Provincial Rail Transit Holding Group Co.,Ltd.,Changsha,Hunan 410017,China)

机构地区：[1]湖南省交通规划勘察设计院有限公司,湖南长沙410200 [2]湖南省轨道勘察设计有限公司,湖南长沙410200 [3]青岛地铁集团,山东青岛266000 [4]江西应用技术职业学院,江西赣州341000 [5]湖南省轨道交通控股集团有限公司,湖南长沙410017

出　　处：《施工技术（中英文）》2024年第6期96-100,共5页Construction Technology

基　　金：湖南省科技创新计划(2022GK4033);湖南省交通运输厅科技进步与创新计划(202014)。

摘　　要：4车道特大公路隧道因其跨高比大,浅埋偏压状况下如何保证工程施工安全,优化其施工工序和发现隧道围岩变形规律有较高研究价值。以单向4车道前鸥隧道为研究背景,通过现场跟踪监测和有限元计算方法,分析不同施工工序变形规律。分析结果表明:先开挖左、右侧导洞再开挖核心土工序产生地表沉降比先开挖上半部再开挖下半部工序产生地表沉降小;不同工序均呈现深埋侧地表沉降大于浅埋侧地表沉降不对称沉降槽;先开挖深埋侧工序比先开挖浅埋侧工序产生的地表沉降小;一次拆除20m竖向临时支撑引起的地表位移及洞周位移均较大,宜减小竖向临时支撑拆除长度;工作面距离观测断面2D(D为初支形成后隧道跨度)时,开挖对变形影响较小,是施作二衬的合适时机。Because of the large span-depth ratio of four-lane super-large highway tunnel,how to ensure the construction safety,and optimize the construction process and find the deformation law of tunnel surrounding rock under shallow-buried bias is of high research value.Taking the one-way four-lane Qianou Tunnel as the research background,the deformation laws of different construction procedures are analyzed through field tracking monitoring and finite element calculation methods.The analysis results show that the process of first excavating the left and right side pilot tunnels and then excavating the core soil produces less surface settlement than the process of first excavating the upper half and then excavating the lower half;The different processes show that the surface settlement on the deep side is greater than the surface settlement of the shallow side(the buried depth is asymmetrical settlement trough);The process of first excavating the deep side of the buried depth produces less surface settlement than the process of first excavating the shallow side of the buried depth;The surface displacement and the displacement around the cave caused by the removal of 20m vertical temporary supports at a time are both larger,the length of the vertical temporary support removal should be reduced;When the working face is 2D from the observation section(D is the span of the tunnel after the initial support is formed),the excavation has less influence on the deformation,and it is a suitable time for the second lining.

关 键 词：隧道工程 浅埋偏压隧道 双侧壁工法 工序 变形 优化 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]