有压引水隧洞多层柔性叠合衬砌对断层蠕滑错动的适应性研究  

Adaptation of multi-layer flexible stacked linings of pressure water transmission tunnels subjected to fault creep

作　　者：徐文韬 徐红超 石长征[1] 伍鹤皋[1] 张超 李端正 XU Wentao;XU Hongchao;SHI Changzheng;WU Hegao;ZHANG Chao;LI Duanzheng(State Key Laboratory of Water Resources Engineering and Management,Wuhan University,Wuhan 430072,China;Central Yunnan Provincial Water Diversion Project Co.,Ltd.,Kunming 650051,China)

机构地区：[1]武汉大学水资源工程与调度全国重点实验室,湖北武汉430072 [2]云南省滇中引水工程有限公司,云南昆明650051

出　　处：《岩土工程学报》2024年第5期998-1007,共10页Chinese Journal of Geotechnical Engineering

基　　金：云南省重大科研专项计划项目(202102AF080001)。

摘　　要：长距离输水隧洞工程建设很难避免穿越活动断层的问题,有压隧洞采用何种衬砌结构型式穿越活动断层迄今为止研究还不够深入。针对目前隧洞过活断层常用抗断措施存在的问题,结合有压引水隧洞自身的特点,提出了一种适合有压引水隧洞穿越活动断层的多层柔性叠合衬砌结构型式。依托某工程的实践情况,采用有限元数值分析方法论证了多层柔性叠合衬砌结构的可行性和合理性;同时分析了垫层厚度、垫层弹模对隧洞结构内力响应和抗断性能的影响。计算结果表明:垫层厚度越大,伸缩节总变形量越大,对于隧洞衬砌适应断层错动越有利;但当垫层厚度过大时,将对衬砌的受力产生不利影响,因此建议根据工程设防的断层错动量选择合适厚度的垫层,不必采用过厚的垫层。垫层弹模的变化对钢管应力的影响较为显著,综合考虑钢衬应力、混凝土损伤以及对断层错动的适应性能,建议选取3~5 MPa的垫层弹模最为合适。研究结果可为有压输水隧洞应对断层蠕滑变形时的结构设计提供参考。Crossing active faults is a difficult problem to avoid when building long-distance water transmission tunnels,and the structural form of pressure tunnels crossing active faults has not been thoroughly studied.In this study,a multi-layer flexible stacked lining suitable for pressure water transmission tunnels crossing active faults is proposed aiming at addressing the problems of the common anti-fracture measures for the tunnels crossing active faults as well as their characteristics.Based on the actual situation of a project,the finite unit method is used to analyze the stress and deformation of the structures under the condition of using different tunnel lining structures in the project.According to the calculated results,the reasonableness of the multi-layer flexible stacked lining structures is confirmed.The numerical simulation is used to assess the impact of cushion thickness and elastic modulus on the internal force response and fracture resistance of the tunnel structures.The findings demonstrate that the thicker the cushion thickness the larger the total deformation of the expansion joints.It is more favorable for the tunnel lining to adapt to fault dislocation.However,when the cushion thickness increases further,there is a certain adverse effect on the force of the lining,so it is recommended to choose the appropriate thickness of the cushion layer according to the amount of fault dislocation.It is not necessary to use a too-thick cushion layer.The change of elastic modulus of cushion has a significant effect on the stress of steel pipes.Considering the stress of steel lining,the damage of concrete and the adaptability to fault dislocation,it is recommended that the elastic modulus of the cushion be selected as 3 to 5 MPa.The research results can provide some references for the design of pressure water transmission tunnels crossing fault zones.

关 键 词：有压隧洞 衬砌结构 断层错动 柔性接头 垫层 数值模拟 

分 类 号：TU43[建筑科学—岩土工程]