Study on Block Safety Evaluation and Treatment Measures of High Natural Slope in Key Region of Wudongde Hydropower Station of Chin-sha River

Environmental geological problems of High slope can often be found in the constructions of hydropower stations in west part of China.Key region of Wu dongde hydropower station is located on Chin-sha River valley which has the shape of narrow "V".The height of the valley is 830~1 036 m,the state of stability not only affects the safety of the construction period,but also be concerned with the safety of the operating of the construction.On the basis of the analysis of field geological investigation,stability problems of some parts of the high slope have been stated briefly.Taking block as example,study on block classification,stability evaluation,safety classification and prevention scheme have been carried out.By the analysis above,some conclusions have been got:firstly,the block classification method based on the unstable mode,as well as the stability evaluation standard based on the block types are put forth;secondly,safety classification principles concerning with the stability of block are got;thirdly,prevention measures on the basis of the comprehensive thinking of the grade,scale,types of block safety and special topographic geological condition have been propounded;last but not least,the new concept of taking out prevention project of high natural slope construction,meanwhile,eliminating the hidden trouble of the safety condition of the construction is brought out creatively,which provides the important basis for the design and construction of the engineering.