盾构下穿既有隧道结构沉降变形数值模拟及参数优化设计  

Numerical Simulation and Parameter Optimization for Settlement Deformation During Shield Tunneling Through Existing Tunnel Structures

作　　者：孙成果 高文 周凯 张箭 梁禹 丰土根[2] SUN Chengguo;GAO Wen;ZHOU Kai;ZHANG Jian;LIANG Yu;FENG Tugen(The Third Engineering Co.Ltd.,China Railway Seventh Group,Xi’an 710000,China;Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210098,China;China Railway South Investment Group Co.,Ltd.,Shenzhen 518052,Guangdong China;School of Civil Engineering,Sun Yat-sen University,Zhuhai 519082,Guangdong China;Key Laboratory for Tunnel Engineering,Guangzhou 510275,China)

机构地区：[1]中铁七局集团第三工程有限公司,西安710000 [2]河海大学岩土力学与堤坝工程教育部重点实验室,南京210098 [3]中铁南方投资集团有限公司,广东深圳518052 [4]中山大学土木工程学院,广东珠海519082 [5]隧道工程灾变防控与智能建养全国重点实验室,广州510275

出　　处：《河南科学》2025年第4期534-542,共9页Henan Science

基　　金：国家自然科学基金项目(52178386)。

摘　　要：城市地下空间的不断开发利用,使得新建盾构隧道交错穿越下穿既有隧道或管线的现象愈发增多,给盾构施工、既有隧道及管线造成一系列不利影响。以深圳某盾构连续下穿既有地铁隧道及综合管廊工程为背景,应用FLAC 3D软件,探讨盾构下穿施工对既有隧道及管廊沉降变形的影响,优化设计盾构参数,并运用于实际工程并结合监测数据验证分析。结果表明:盾构下穿施工过程中引起既有隧道与综合管廊的变形以竖向沉降为主,远离交叉区的结构两侧呈现隆起,此过程中既有建筑存在扭转变形;由于时空效应,竖向位移将会继续发展,直至达到最大沉降值;盾构下穿综合管廊造成的结构底部变形速率要小于穿越既有隧道的变形速率,对下穿该区段必要时需采取合理的加固措施;盾构下穿施工盾构推进注浆压力和土仓压力主要影响区域分别为距既有隧道1.0~2.0倍、1.5~2.0倍洞径左右范围,在此范围内最大沉降量与注浆压力和土仓压力均呈负相关关系,此范围以外既有隧道沉降量所受影响较小。With the continuous development and utilization of urban underground space,shield tunnels increasingly intersect with existing tunnels or pipelines,leading to various adverse effects on shield construction,as well as on existing tunnels and pipelines.Based on a shield tunneling project beneath existing subway tunnels in Shenzhen,this study employs FLAC3D software to investigate tunnel and pipeline deformations caused by shield construction.It optimizes shield parameters to mitigate subsidence and applies the optimized parameters in real projects for verification and monitoring analysis.The optimized shield parameters are applied to actual projects and verified through monitoring data analysis.Results indicate that the deformation of existing tunnels and the integrated pipeline corridor due to shield tunneling is primarily characterized by vertical settlement.Additionally,structural sections away from the crossing area exhibit bulging,while existing buildings undergo torsional deformation during the process.Due to spatial and temporal effects,vertical displacement continues to develop until reaching its maximum settlement value.The deformation rate at the bottom of the structure caused by shield tunneling under the integrated pipeline corridor is lower than that of the existing tunnel.Therefore,optimizing shield parameters is essential for safe penetration of this section,and verification should be conducted using real project monitoring data.Appropriate reinforcement measures should be implemented when necessary.The primary influence zone of grouting pressure and soil pressure during shield tunnel construction is approximately 1.0-2.0 times and 1.5-2.0 times the diameter of the existing tunnel,respectively.Maximum settlement is negatively correlated with both grouting and soil pressure,and settlement of existing tunnels beyond this range is less affected.

关 键 词：盾构隧道 既有隧道 既有管线 数值模拟 变形规律 

分 类 号：TU432[建筑科学—岩土工程] TU942[建筑科学—土工工程]