Study of Block Stability of Surrounding Rock Mass of Main Transformer Chamber Based on VATS Program

摘要

The fracture of rock mass for main transformer chamber in HuangGou hydropower station is very developed. The blocks slide along the discontinuous face or free face with the excavation of cavern. It leads to the failure of normal construction. In the study, according to geology of disclosed discontinuous face in detecting cavern and local three-dimensional coordinate of underground caverns, the vector analysis program for tunnel stability VATS is compiled by using the method of vector analysis of the block theory which is applicable to analyze the discontinuous rock mass and numerical software MATLAB. The occurrence of joints, the coordinate of measuring point, the radius and vertical wall height of underground caverns and other relevant engineering datum is required to input the program. The combination of discontinuous face, boundary condition, geometric parameter, the mode of failure and stability factor of existent unstable blocks is obtained. The geometry distributing characteristic of block and key discontinuous faces in different position is figured by the AUTOCAD software. The guidance for construction of underground caverns is provided.