Study On Stability Of Jinsha River Hydropower Station Guanyinyan High Dam Dam

Guan Yinyan hydropower station is the final cascade pumping station of eight cascade planned of middle reach of the jinsha river, upstream is Cohesion with LuDila hydropower station, downstream is WuDongde hydropower station, The most important feature of the Guan Yinyan hydropower station is gravity dam mix with core rockfill dam. The highest dam is149m, reservoir is100kilometres, belongs to canyon-reservoir, and The installed size is3000MW。The research object in this paper is the rock mass of dam foundation of high dam section at the left of Guan Yinyan hydropower station, Starting from the analysis of engineering geological conditions, research engineering geological characteristics of dam foundation through mass field measurement data and experimental data, rock mass quality classification, determined grading standard, then, Through the methods of numerical modeling on the level of two dimension and three-dimensional to Analysis the stability against sliding, Through the above research, The main achievements are as follows:(1) The dam foundation of Guan Yinyan hydropower station is high-steep and layered rock mass, different layer rock mass Cross each other, structure of rock mass follow the reciprocal changes of lithology, most sandstone and conglomerate are Thick-bedded—giant Thick-bedded, great majority of siltstone is mediumaltitude bombing bed, the bulk pelite is thin layer—interbed。(2) Development of structural plane majority, steep Angle and vertical plane transverse joint almost development at conglomerate strata; minitype Flat surface structure development at some places, there are two Ⅲ level Controllability Flat surface structure of stability of dam exposed In the late excavate extended length nearly200meters。(3) The degree of weathering and unloading,rock mass structure,uniaxial compression strength of saturated rock,longitudinal wave velocity,deformation modulus and shear strength are selected as the rock mass quality classification index.The dam foundation is mainly Ⅱ and Ⅲ class,but part of rock decrease to Ⅳ class for the corrosion and the severe is V class.·(4) Two-dimensional and three-dimensional geological models were established to analyse the anti-slide stability of the dam foundation. And under different condition,we analyse the stress and strain of the vital areas including dam heel and dam toe.Then this paper uses the shear strength reduction method and rigid body limit equilibrium method to calculate the anti-slide stable coefficient of the dam foundation.And the result is less than3,which is anastomotic to the standard.According to the result,the rock quality of the dam foundation, located in Guan Yinshan Hydroelectric Power Station, is pertty good.Andaffected by faults F1the high dam on the left bank is stable.all of these satisfy the design requests.