Rock Classification Of Diversion Tunnel Study Of Jinping â…¡ Hydropower Station In Yalong River

Along with the unceasing development of economy and technology,underground space empoldered and used has never achieved the extent.As a example of this article,the maximal embedded depth of the diversion tunnel in Jinping waterpower station is 2525m. The ground stress is greater than 70MPa.And the underground water is greater than 10MPa.Because the existing surrounding rock mass classification methods can't adapt the complicated geoenvironment,a new classification method must be researched.The new classification method can adapt the geoenvironment high ground stress and the high external water pressure.To Jinping Hydropower Station on the Yalong River diversion tunnel to study rock classification, this paper first line of the diversion tunnel projects to conduct a detailed geological conditions, the excavation has been completed on long exploratory tunnel, auxiliary hole rockburst brief summary summary of diversion tunnel and the rock burst prediction brief, follow-up section for papers diversion tunnel study of rock classification for reference. Jinping then rock classification (JPF) system and related parameters are briefly introduced and explained. The classification system will be applied to the rock under complicated geological conditions Jinping has completed excavation of the auxiliary hole for authentication, get a better match rate.The basis of the foregoing, this article jinping the rock classification system applied to the larger diameter of the diversion tunnel in the rock classification for validation and research. Rock classification and validation study results through the application of rock classification, relevance and consistency of.Jinping first rock classification system for the application of water 4 # hole has opened a hole section of rock classification, the results of classification of rock types and on-site to verify the match rate jinping the applicability of rock classification system, the adoption of the authentication system, we can see, JPQ system of classification and the selected category of rock above the hole was 83.5% with different stress-section of more than 78.6% for the different lithologies in the paragraph above 82.4%, to better reflect the project area jinping the actual situation; JPRMR system statistics and classification results of the selected rock types of holes with paragraph rate of 82.2 percent, in the highlands rockburst stress is only 66.8% above that in T1, T2Z formation only 66.7% ~ 77.1%; JPHC system of classification and the results of the selected hole and rock above categories with 87.3 percent rate, different stress-section more than 83.4 percent for different lithology is also up to more than 83.8 percent, better classification results can reflect the auxiliary hole rockburst, groundwater and the structure of the face of an adverse impact on stability of surrounding rock, and its share of various types of rock ratio close to the actual rock types on the applicability of good JPHC classification. This is the JPF to JPHC-based classification system in order to supplement the JPQ and JPRMR reasons jinping rock classification system is very good applicability; Second, through the classification of the relevance of the results to verify and research, Classification results based on correlation analysis, we can see: JPQ, JPRMR and JPHC three classifications of water 4 # hole in the western section of open hole in the correlation coefficient between 0.72 ~ 0.77, a good correlation, and in the water 4 # hole to open hole section of the eastern part of the correlation coefficient between the 0.859 ~ 0.879, very good correlation, statistical analysis shows that the use of JPQ, JPRMR and contrast each other JPHC authentication is reliable and able to meet under complicated geological conditions jinping rock classification needs. Finally, we can see through consistency analysis: 4 # diversion tunnel digging paragraph open JPQ, JPRMR and classification of three JPHC score values normalized after the basic difference in the [-0.1,0.1] interval changes. Water 4 # dig holes to open the western section of the absolute difference between the averageΓin [0.05,0.1], between the reliability ofαhas been less than 0.1 indicating a good consistency of the selected paragraph holes, while the eastern part of water 4 # hole burrow opening paragraph of the absolute difference between the averageΓin [0,0.05], between the reliability ofαhas been also less than 0.1 indicating a good consistency of the selected paragraph holes. Can be seen, JPQ, JPRMR and verify the effect of contrast JPHC good.At the same time make use of the existing excavation has been completed and part of the supporting hole of the diversion tunnel excavation engineering geology data, rock type of comparative data, lithological boundaries, such as comparative analysis of relevant research data, using linear interpolation method to auxiliary burrow hole opening paragraph has been rock category corresponds to the diversion tunnel, the achievement of the diversion tunnel rock classification prediction.In order to further study of deep surrounding rock types In order to further study the size effect of deep tunnel, I would have finished the excavation of the long exploratory tunnel, auxiliary water hole and open hole section of tunnel surrounding rock classification comparative analysis. Comparative analysis of results showed that: rock types of statistics show that the same type of long-hole exploratory tunnel, auxiliary A, B-dong, diversion tunnel rock category with the overall increase in cavity size decreased, analysis and comparison of numerical simulation results show that the surrounding rock deformation With increasing cavity size and the corresponding increase. Rock types of statistical and numerical analysis and comparison of the relationship between simulation results show that the shape of the chamber the same size as the chamber increases, rock types of the corresponding reduction of the diversion tunnel and round the same size and basic auxiliary hole hole B compared to a decline of surrounding rock deformation, rock types has increased, a circular chamber that is more conducive to the stability chambers.