Evaluation On Stability Of Soil Slope In Reservoir Of Da Gang Muntain

Da Gang Shan hydroelecteic station is a typical one in southwest of China,where the engineering geological conditions are very complicated. Therefor the bank recession is a basic part of the geological disaster in this area.The bank in this area consist of two parts: soil bank and rock bank. Most bank recession take place in soil bank. The soil bank may be summarized two type: colluvial deposit and accretion. The different original cause provide them different characters on colluvial deposit stability and stability under water.Bank recession is a very complicated course,which consist of bank slope failure under seris of conditions and abrasion actions. Base on this point,the author make his study from stability and abrasion of the bank.Firstly the thesis made study on stress field, displacement field, yielding part in colluvial deposit and accretion before water accumulated and after water accumulated and made the conclusion that slope failure will take place easier in colluvial deposit than in accretion.The stability computation indicates that stability will decline either for colluvial deposit or accretion bank and decline more rapidly in colluvial deposit than accretion bank. Another conclusion is that stability is better in accretion bank than in colluvial deposit bank.A comprehensive study has been made on the course of reservoir bank recession on the theory of fluvial and wave dynamic mechanics with a view of character of mountain land. Some appraise and rectifying suggestions for current methods are given by computing the scale of the bank recession in the area.As the theory of bank recession in mountain land is not mature,the conclusions got is instructive to the theory on bank stability and bank recession by the comprehensive study on bank stability in Southwest of China,especially in Si Chuan Pro.