考虑渗流效应的衬砌隧洞围岩弹塑性分析  

Elastic-Plastic Analysis of Surrounding Rock of Lining Tunnel Considering Seepage Effect

作　　者：孙河林 姜海波[1] SUN Helin;JIANG Haibo(College of Water Conservancy&Architectural Engineering,Shihezi University,Shihezi 832003,Xinjiang,China)

机构地区：[1]石河子大学水利建筑工程学院,新疆石河子832003

出　　处：《隧道建设（中英文）》2023年第S01期206-215,共10页Tunnel Construction

基　　金：国家自然科学基金项目(51769031);兵团区域创新引导计划项目(2021BB004)。

摘　　要：为探明孔隙水对施工期水工隧洞稳定性的影响,基于弹塑性理论,采用Mogi-Coulomb强度准则,以衬砌-围岩弹塑性区为研究对象,推导圆形隧洞不同工况时围岩-衬砌结构应力、隧洞洞壁位移和围岩塑性区半径的解析解。依托新疆某水工隧洞工程展开计算分析,得到渗流效应、衬砌渗透系数和衬砌厚度对围岩-衬砌结构稳定性的影响规律。得出以下结论:1)渗流作用会极大改变衬砌和围岩的应力分布,减小衬砌对围岩的支反力会使隧洞稳定性变差;2)降低衬砌渗透系数会增大衬砌-围岩交界面渗透水压力,减小支反力会使围岩塑性区半径和洞壁位移有所增大;3)增加衬砌厚度会改变渗流场分布,弱化增加衬砌厚度提供的支护增幅效果,这在开始阶段能明显限制围岩塑性区发育,但后续效果不佳。In order to study the influence of pore water on the stability of hydraulic tunnel during construction,the MogiCoulomb strength criterion is adopted based on the elastic-plastic theory,and the elastoplastic zone of lining-surrounding rock is taken as research object.The analytical solutions of circular tunnel under different working conditions are derived,including the stress of surrounding rock-lining structure,tunnel wall displacement,and surrounding rock plastic zone radius.Relying on a hydraulic tunnel project in Xinjiang,the calculation and analysis are carried out to obtain the influence laws of seepage effect,lining permeability coefficient,and lining thickness on the stability of surrounding rocklining structure.The conclusions are as follows:(1)Seepage effect will greatly change the stress distribution of lining and surrounding rock,reducing the support reaction of lining to surrounding rock can worsen the tunnel stability.(2)Reduction of the lining permeability coefficient will increase the seepage water pressure at the interface between lining and surrounding rock,reducing the reaction force can increase the radius of surrounding rock plastic zone and tunnel wall displacement.(3)Increasing the lining thickness will change the distribution of seepage field and weaken the support amplification effect caused by increasing lining thickness,which can significantly limit the development of surrounding rock plastic zone in the initial stage,but the subsequent effect is poor.

关 键 词：Mogi-Coulomb强度准则 圆形隧洞 围岩-衬砌结构 渗流效应 衬砌渗透系数 衬砌厚度 

分 类 号：U45[建筑科学—桥梁与隧道工程]