Stability Study To 2# Ripping Loose Rock Mass Slope Of Yagen Hydropower Station

Yagen hydropower station is the controlling power plant reservoir engineering of middle and lower reaches of the Yalong River, the whole cascade Yalong impact on the development of power plants tremendously. 2# ripping loose rock mass slope lies in the front of the dam, and it takes on obvious deformation. So, studying the mechanisms of deformation and damage and assessing the slope stability have important practical significance, to ensure the normal operation of power plants.Based on the study of the basic geological conditions , rock structure, deformation and fracture of signs of 2# ripping loose rock mass slope, this paper analyses the slope deformation and failure mode and the causes of the mechanism, and simulates the causes of the mechanism. Based on qualitative judgments of its stability, the paper accounts and estimates the stability of the slope by use of limit equilibrium theory, and put forwards some suggestions. Details and results are as follows:(1)The paper maked a more comprehensive summary of the characteristics of rock mass structure and established the geological structure of the model. The structure is divided intoⅢ,Ⅳ,Ⅴlevel structure and the characteristics of their characters are described in detail. According to the structure of spatial differences, the valley slope isdivided into two sub-areas:Ⅲ-1 andⅢ-2, respectively, on the structural characteristics of the area. the deformation and damage of 2# ripping loose rock mass slope is mainly affected by N10-30W/NE∠14-25°and N45-70W/NE∠25-35°, showing thick flat plate structure, the main damage mode is slip (pressure-induced) crack type.(2)Studying the deformation and fracture characteristics of slope particularly, summarizing the slope geo-environmental conditions, combined with quantitative index, the paper determines the borderline of 2# ripping loose rock mass. (3)Controlled by lithology, rock structure, high geo-stress and Geomorphic Evolution, through the causes analyses of the Low-angle structure, it is indicated that 2# ripping loose rock mass is special rock under high geo-stress, and it is formded by Superficial Health Reform. Using Numerical simulation of finite element, the paper studied the formation of 2# ripping loose rock mass.(4)The research shows that 2# ripping loose rock mass slope is stable in whole, but it has little safety margin, which is validated by Limit equilibrium theory. 2# ripping loose rock mass is stable in natural conditions and heavy rain conditions; it is potential unstable in earthquake and in the water conditions. Using Numerical simulation confirmed the geological judge and limit equilibrium calculation.(5)Based on the evaluation findings, recommendations are as follows: Further exploration shoud be planned to determine the borderline of 2# ripping loose rock mass well; The stability and the measures should be studied; The distortion should be inferred.