上软下硬复合地层盾构隧道开挖面稳定性分析  

Stability analysis of excavation face of shield tunnel in upper soft and lower hard composite strata

作　　者：叶友林[1] 刘晓龙 牛奔 周广宇 徐春一[2] YE Youlin;LIU Xiaolong;NIU Ben;ZHOU Guangyu;XU Chunyi(School of Transportation Engineering,Shenyang Jianzhu University,Shenyang 110168,Liaoning,China;School of Civil Engineering,Shenyang Jianzhu University,Shenyang 110168,Liaoning,China;China Construction Sixth Engineering Bureau Co.,Ltd.,Tianjin 300451,China)

机构地区：[1]沈阳建筑大学交通学院,辽宁沈阳110168 [2]沈阳建筑大学土木工程学院,辽宁沈阳110168 [3]中国建设第六工程局有限公司,天津300451

出　　处：《沈阳工业大学学报》2024年第6期848-854,共7页Journal of Shenyang University of Technology

基　　金：国家自然科学基金项目(52008269);辽宁省博士科研启动基金项目(2024010136-JH3/101)。

摘　　要：针对上软下硬复合地层条件下盾构隧道开挖面的稳定性问题,依托深惠城际2标实际工况,分析不同软硬比及土体参数对开挖面极限支护压力的影响。利用颗粒流数值模拟分析土体的失稳模式,借助极限分析法建立符合开挖面失稳轮廓的理论计算模型,将理论计算结果与既往文献及实际工程进行比较分析。结果表明:当隧道开挖面主动失稳时,变形主要集中在软土层,硬岩层的变形较少;随着开挖面软硬比的增大,隧道开挖面的极限支护压力也增大;开挖面的极限支护压力与隧道埋深比无关,与土体内摩擦角成反比。Aiming at the stability of shield tunnel excavation face under the condition of upper soft and lower hard composite strata,and according to the actual working conditions of Shenzhen-Huizhou Intercity Railway Section 2,the influence of different soft-hard ratios and soil parameters on the ultimate support pressure of excavation face was analyzed.The instability mode of soil was analyzed by using particle flow code(PFC)simulations,and a theoretical calculation model consistent with the instability profile of the excavation face was established by using limit analysis method.The theoretical calculation results were compared and analyzed with previous literatures and practical engineering.The results show that the deformation is mainly concentrated in the soft soil when the tunnel excavation face actively loses stability,whereas the deformation of hard rock is comparatively minor.As the soft-hard ratio of excavation face increases,the ultimate support pressure of tunnel excavation face also increases.In addition,the ultimate support pressure of excavation face is independent of the tunnel burial depth ratio but inversely proportional to the internal friction angle of the soil.

关 键 词：盾构隧道 离散元 上软下硬复合地层 极限分析法 开挖面稳定性 埋深比 内摩擦角 软硬比 

分 类 号：TU432[建筑科学—岩土工程]