改进的遍布节理模型及其在层状岩体地下工程中的应用

基于显式有限差分程序FLAC3D，针对层状岩体建立了可以考虑其横观各向同性变形特性的遍布节理模型。通过FLAC3D程序的预留接口导入程序，将该改进的遍布节理模型中植入FLAC3D动态链接库。在此基础上进行了层状岩体变形与强度各向异性特性的研究，最后将该模型应用于龙滩水电站巨型地下硐室群的层状岩体围岩变形及破裂特征分析。研究表明，围岩变形主要表现为岩层同性面内的变形，其左右边墙变形不对称性主要受断层切割控制；围岩破坏型式以剪切破坏为主，其中岩体整体破坏受断层控制，表现为中低应力条件下的拉剪或压剪破坏；而开挖引起的岩层破坏受制于陡倾角层状岩体结构，表现为层间错动引起的剪切破坏。

Improved ubiquitous-joint model and its application to underground engineering in layered rock masses

An improved ubiquitous-joint model, which can take into account of the transversely isotropic deformation characteristic of the layered rock masses, is established. By using the program’s reserves connection, this new model is implanted into the explicit finite-difference program FLAC3D, and the anisotropy of deformation and strength of the layered rock masses are studied. Then, the deformation and fracture characteristics of the layered rock masses of the Longtan hydropower station underground caverns are studied based on the improved model. The results show that the dominating deformation occurs in the isotropic plane of the rock masses, and the asymmetric deformation of the side wall are controlled by the faults. The main failure of the surrounding rock masses is shear failure which is also controlled by the faults and primarily presents the tensile-shear failure and the compression-shear failure under the moderate and low stress. The joint failure that caused by the excavation process are controlled by the steep dip layered rock mass structure, which primarily presents the shear failure caused by intercalated sliding.