南水北调西线工程板岩强度的各向异性特征

ANISOTROPY OF SLATE STRENGTH IN WEST ROUTE OF SOUTH-TO-NORTH WATER TRANSFER PROJECT

南水北调西线工程区域内岩体类型主要为砂岩、板岩,其中板岩强度特性具有明显的各向异性特征。研究复杂地质条件下板岩的强度特征及变形规律,确定合理的板岩强度参数,对于引水坝址的选取和深埋长隧洞的设计与施工都具有十分重要的意义。在南水北调西线工程选取钻孔采取的板岩岩样,通过单轴压缩变形试验和三轴压缩试验等室内试验方法,借助Hoek-Brown经验破坏准则,对板岩强度随板理面倾角的变化规律、板岩强度的各向异性特征进行了分析,并确定了合理的板岩抗剪强度参数。研究成果可为工程设计提供必要的基础资料。

Sandstone and slate are the main rock types in the west route area of the South-to-North Water Transfer Project.The strength of slates is anisotropic obviously.It plays a significant role in the choice of the diversion dam site and the design and construction of the deep and long tunnelsThis paper studies the strength characters and deformation law of slates,and confirms the reasonable strength parameters of slates.The uniaxial compression deformation tests and triaxial compression tests are carried out on slate samples drilled in the west route area.The study considers the various laws of the slate strength with the dips of bedding planes.The anisotropy of the slate strength is obtained with the Hoek-Brown criterion and based on these test results.The shear strength of the rock mass is confirmed and becomes the foundation for engineering design.