Stability Analysis Of Surrounding Rock Mass And Anchorage Of Underground Caverns

The stability of surrounding rock and the design of reinforcement of underground cavern are the key technique of underground projects. With the development of computer technique, a big progress has been made on analyzing the stability of surrounding rock and anchorage of underground caverns using numerical simulation method. There are a lot of numerical techniques and simulation software which can be used in analyzing the stability of surrounding rocks and bolting effect of underground caverns. But because of the characteristics of FDM (Finite Difference Method), it is more suitable in calculating the stress and strain problems of rock and soil. FLAC which based on FDM is one of the most popular software which can be used in analyzing the stability of surrounding rocks and bolting effect.This dissertation was composed with three parts. The first one about is the theory preparation. The stability of surrounding Rock and the force of bolt were discussed firstly, then the theory basement of FDM and the software FLAC were studied, at the last of this part, the factors which affect the reinforcement and how to evaluate the effect anchorage quality were analyzed. The second part is how to choose the parameters of anchorage. It's very difficult to choose the parameters of bolting in numerical simulation because there are no criterions in the field of hydropower engineering in China, most of the parameters were decided by engineering experiences. A lot of cases were simulated by FLAC, and the space and the length of bolt were the research focus. The results of numerical simulation accord with the parameters which were used in most of hydropower engineering, and the results also were compared with the recommended parameters by Barton's "Q" system. In the last part of this dissertation, the bolting parameters from FLAC calculation were used in FLAC~3Dcalculation. Excavation and bolting analysis of an underground cavern project in south-west in China were simulated through FLAC~3D; the result can provide certain instructional significance to the design and construction of the engineering.