盾构下穿施工对既有盾构隧道结构的影响研究  

Influence of shield under-crossing on structure of existing shield tunnel

作　　者：陈向阳[1] 张雯超[1,2] 赵西亭 陆俊 吴生海[1] CHEN Xiangyang;ZHANG Wenchao;ZHAO Xiting;LU Jun;WU Shenghai(School of Architectural Engineering,Nantong Vocational University,Nantong 226007,China;School of Rail Transit,Soochow University,Suzhou 215131,China;North Information Control Research Institute Group Co.,Ltd.,Nanjing 211153,China)

机构地区：[1]南通职业大学建筑工程学院,江苏南通226007 [2]苏州大学轨道交通学院,江苏苏州215131 [3]北方信息控制研究院集团有限公司,江苏南京211153

出　　处：《人民长江》2021年第12期126-132,共7页Yangtze River

基　　金：国家自然科学基金项目(51978430);广东省基础与应用基础研究基金区域联合基金-青年基金项目(2019A1515110836);南通市科技项目(MS12019050)。

摘　　要：新建隧道近距离下穿既有盾构隧道,不可避免会引起上方既有隧道的变形沉降,改变隧道结构的受力状态。隧道纵向抗弯刚度是隧道纵向变形、结构设计的重要参数之一。对比分析了一系列纵向等效刚度的计算模型,并通过三维数值模拟研究盾构下穿施工对上方既有隧道在不同计算模型下的沉降以及受力的影响。通过现场监测验证了各计算模型在工程中的适用性,最后选取适合北京地铁12号线工程的计算模型进一步分析了盾构超挖对上方既有隧道的沉降影响规律。研究表明:随着地层损失增加,既有隧道沉降随之增大,归一化的既有隧道最大沉降与地层损失率呈线性关系。When a new tunnel under-crosses an existing shield tunnel,it inevitably causes the deformation and settlement of the existing tunnel and changes the stress state and distribution of the tunnel structure.The longitudinal equivalent stiffness of the tunnel is one of the important parameters in the longitudinal deformation and structural design of tunnel.In this paper,a series of calculation models of longitudinal equivalent stiffness were compared and analyzed.Through 3D numerical simulation,the influence on the settlement and the force of the existing tunnel by different calculation models was studied.The applicability of the calculation model for the Beijing No.12 railway project was verified by field monitoring,and finally the suitable calculation model was selected to further analyze the settlement law of shield under-crossing on the existing tunnel.The results showed that the settlement of existing shield tunnel increased with the increase of stratum loss,and the normalized maximum settlement of existing shield tunnel had a linear relationship with the stratum loss rate.

关 键 词：盾构下穿施工 纵向等效刚度 受力变形 超挖 数值模拟 

分 类 号：U231[交通运输工程—道路与铁道工程]