富水板岩隧道围岩泥化临界判据研究

在地下水的影响下，板岩隧道围岩会发生泥化作用，然而目前规范中在对富水板岩隧道进行衬砌结构设计和围岩变形计算时，将泥化前后两种状态视为一种状态，忽略了泥化的影响。课题以沪昆客运专线长昆湖南段姚家隧道为工程依托，以板岩为研究对象，借助微细观试验探寻板岩矿物成分、微观组构和孔隙结构的泥化演变规律；基于水理性试验建立板岩泥化膨胀本构方程及研究其泥化过程中崩解产物塑性指数和颗粒粒度的变化特征；通过三轴压缩和水岩化学试验研究水化学参数、水压力、吸水率和结构面产状对板岩力学参数的劣化效应，分析应力路径对板岩泥化的影响。在此基础上运用突变理论和混沌理论建立富水板岩隧道围岩泥化临界模型，为修正计算富水板岩隧道衬砌结构和围岩变形提供依据。

Under the influence of groundwater, argillization of surrounding rock in slate tunnel will happen. However, the current specification on lining structure design and surrounding rock deformation calculation in water-rich slate tunnel regarded two kinds of state (before and after argillization) as one state and ignored the influence of argillization. The project takes Yaojia tunnel in Shanghai-Kunming Passenger Dedicated Line Chang-Kun Hunan Section as the engineering background and slate as the research object. The argillitization evolution of slate mineral content, microstructure and pore geometry is explored using mico-meso test. The argillitization swelling constitutive equation is established, and the evolution characteristics of the plasticity index and the particle size for disintegration product in the mudding process is researched based on hydro-physical test. The degradation effect of the hydro-chemical parameters, water pressure, water absorption and the structural plane occurrence on the mechanical parameters is studied, and the influence of stress path on slate argillitization is analyzed through triaxial compression test and water-rock chemical experiment. Then the catastrophe and chaos theory are used to establish the argillitization critical model of surrounding rock in water-rich slate tunnel, providing the basis for revising calculation of lining structure and surrounding rock deformation in water-rich slate tunnel.