Selection of Methods for Predicting Bank Collapse of Ice-Water Accumulations in Alpine Canyon Area of Southeast Tibet
Due to the strong carrying capacity of glaciers and the short accumulation path,ice-water deposits are prone to structural fragility and rapid attenuation of cohesion.Therefore,the stability of the reservoir bank slope under the influence of external forces of ice-water deposits is quite different from that of traditional strata,and the existing bank collapse prediction method cannot be directly applied for the calculation of the reservoir bank slope.Taking the reservoir bank slope of a hydropower project in Tibet as the object,the accuracy of different bank collapse calcu-lation methods in the calculation of ice-water deposits is analyzed through field tests,numerical simulation and other methods.The results show that the calculation results of the two-stage method and the flush-pile balance method differ by 3 times(6.2 million m3 and 2.18 million m3 re-spectively),and the prediction results of the flush-pile balance method are closer to the actual bank collapse volume after water storage;the bank collapse volume of the unstable slope in the reservoir area is 2.33 million m3,which is close to the prediction result of bank collapse volume by the flush-pile balance method.Therefore,the flush-pile balance method meets the calculation requirements of bank collapse of ice-water deposit reservoirs,and can provide reference for the design and management of reservoir slopes in mountainous canyon areas.