基于夹层理论的地铁隧道防水型单层衬砌叠合结构受力分析  

Stress Analysis of Waterproof Single-layer Lining Composite Structure in Metro Tunnels Based on Intermediate Layer Theory

作　　者：温书亿 邓一三 WEN Shuyi;DENG Yisan(China Railway Academy Group Co.,Ltd.,610031,Chengdu,China)

机构地区：[1]中铁科学研究院集团有限公司,成都610031

出　　处：《城市轨道交通研究》2024年第8期192-199,共8页Urban Mass Transit

基　　金：中国中铁股份有限公司项目(2021-重大-15)。

摘　　要：[目的]喷涂防水膜可使地铁隧道衬砌中混凝土与防水膜发生复合作用,然而目前还没有关于防水型单层衬砌叠合结构分析的设计指导和参考文献。提出了基于夹层理论确定隧道单层衬砌叠合结构厚度及按照刚度进行弯矩分配的设计方案。[方法]首先进行了等效厚度及弯矩分配理论推导,并选择青岛地铁1号线西镇站进行等效厚度及各层弯矩分配计算,得出理论解析解。为了验证理论的正确性,使用有限元软件Ansys进行了数值仿真分析,对第二层喷射混凝土在不同厚度情况下的等效厚度、弯矩分配情况进行了比较和讨论。最后采用室内试验方法,针对夹喷涂防水叠合结构与不夹防水层的结构进行四点梁对比测试,通过夹层抗弯强度折减比例反算夹层结构的等效厚度。[结果及结论]采用所设计方法可以确定等效厚度及弯矩分配,该方法合理可行。[Objective]The application of sprayed waterproof membranes can enable composite action between the shotcrete and the waterproof membrane in metro tunnel linings.However,there is currently no design guidance or reference literature for analyzing waterproof single-layer lining composite structures.A design method is proposed to determine the thickness of the tunnel single-layer lining composite structure and to allocate bending moments according to stiffness based on intermediate layer theory.[Method]The theoretical derivation of equivalent thickness and bending moment distribution is first conducted.The Qingdao Metro Line 1 Xizhen Station is selected for calculating the equivalent thickness and bending moment distribution of each layer,yielding theoretical analytical solutions.To verify the accuracy of the theory,numerical simulation analysis is performed using the finite element Ansys,comparing and discussing the equivalent thickness and bending moment distribution for different second layer shotcrete thicknesses in tunnels.Finally,indoor experiments are conducted to perform four-point beam tests comparing structures with and without a sprayed waterproof membrane.The equivalent thickness of the composite structure is calculated through the reverse deduction of the bending strength reduction ratio of the intermediate layer structure.[Result&Conclusion]The proposed design method can accurately determine the equivalent thickness and bending moment distribution,proving to be both reasonable and feasible.

关 键 词：地铁隧道 防水型单层衬砌 夹层理论 喷涂防水 

分 类 号：U455.91[建筑科学—桥梁与隧道工程]