Underground Planthouse Surrounding Rock Stability Study Of Xiangjiaba Hydropower Station In Jinsha River

With the rapid development of our national economy and the state of infrastructure construction investment continued to expand, in water conservancy and hydropower, railway, highway, mines and other projects in the field of underground engineering quantity is getting more and more, the scale is also growing, in order to make the design of tunnel support both safe and economical, safe, reliable, effective analysis and evaluation of the stability of the caverns is particularly important. Many domestic and foreign underground rock engineering examples shows that the modern numerical analysis methods, the progress, the rapid development of the computer, have been able to better solve the geological structure is complex, the shape of a variety of large cavern surrounding rock stability calculation, influence the stability of surrounding rock of tunnel to evaluate the effect of the leading factors has shifted to the cavern rock mechanics environment. Therefore, thorough, meticulous job to rock mass structure indexes of investigation, measurement, the right choice at home and abroad have extensive application and to obtain good results of surrounding rock classification system, completes the surrounding rock classification, in accordance with the surrounding environmental conditions established in accordance with the actual mechanical model of rock mass; on the basis of analysis and evaluation of stability of surrounding rock, evaluation of underground cavern surrounding rock stability is the main technical method.Xiangjiaba Hydropower Station Underground Powerhouse cavern surrounding rock with large flat layered structure, rock developed in the gentle interlayer fractured mud layer, stability of surrounding rock is the key research project needs to resolve the outstanding engineering geological problem. This paper analysis the study area in the extensive collection of drilling, hole exploration, geophysical prospecting, rock physical mechanics test and stress test and other large exploration test data base, system, thorough ground to begin the rock mass structure index survey, survey work; using GB50287-99" water conservancy and hydropower engineering geology." the surrounding rock classification method, recommended as well as international common geological mechanics of surrounding rock classification method (RMR) and surrounding rock quality classification method (Q), on the surrounding rock classification; according to the rock mass structure and surrounding rock type reasonable selection of mechanics parameters, to establish a more credible rock mechanics model; using the macro analysis, based on the qualitative analysis of rock mass structure the space projection, block stability analysis and three-dimensional discrete element method (3DEC), of Xiangjiaba underground powerhouse cavern stability of surrounding rock. For the design of tunnel support and excavation provides credible basis.