Rock Relaxation Preliminary Study On The Dam Bedrock Of Jinping One-Level Hydropower Station

Jinping hydropower station arch dam is of similar construction in the world highest dam. As the steep bank slope of Jinping dam site, excavation of large, complex body excavation, foundation rock unloading and relaxation is very conspicuous. In this paper, the prototype research and laboratory analysis, system analysis and simulation of the combination of ideas. Foundation excavation process on the basis of processing chamber exposed lining cracking caused relaxation of the rock mass, burst before and after the burst test data Vp, Vp rock dam and Numerical Simulation of the Long View data analysis approach. Hydropower Station Dam Foundation Rock on relaxation characteristics of the preliminary research. Specific contents and results are as follows:(1) foundation excavation process, on the basis of processing chambers lining the left bank of cracking phenomenon in depth investigation on crack growth characteristics of lining a detailed study and analysis. The results showed that: As the basis for processing prior to tunnel construction, foundation excavation, foundation excavation unloading is the left bank of the foundation treatment of the role of cavity lining one of the major crack, crack distribution through the lining of the unloading and relaxation to judge the impact of depth.(2) rock burst through the dam before and after the explosion Vp test data, the use of engineering methods of statistical analysis of the blasting of the rock mass relaxation effects. General relaxation of rock blasting between the depth of 0.5 ~ 2.5m, while blasting rock at different levels of rock relaxation quite different.(3) to contrast this view of hole wave length changes the method of dam foundation rock mass relaxation of the depth of the study, from the strength and deformation point of view of quantitative parameters of the timeliness of dam foundation rock mass relaxation characteristics were analyzed to clarify the foundation rock body of laws and the development of relaxation factors.(4) using numerical simulation methods, the establishment of a foundation FLCA3D model to simulate the process of foundation excavation, foundation excavation and analysis of excavation after the stress and displacement variation. The results showed that: after the excavation of dam foundation rock mass stress relaxation of the overall change was a decline trend. Foundation excavation, the displacement mainly for the upward rebound unloading deformation, and both relaxation to the excavation free face deformation.