Bank Slump Model And Range Prediction Of Different Loose Accumulated Slops In Qiaoqi Reservoir

There are different kinds of loose accumulation slopes in reservoir area of Qiaoqi Hydropower station. In the period of water storage and water drainage, the different loose accumulation slopes had happened different bank slump. In this thesis, taken the (?)accumulation,(?)accumulation and (?)accumulation as the main objects of study, in field survey we had measured the underwater stable slope angle of different loose accumulations during the medium-term of reservoir running. And we had taken the samples to do grain-size composition analysis on different loose accumulation slopes. We adopt the field investigation and test analysis to study the basic geological characteristics, and analysed the relationship between underwater stable slope angle and grain-size composition, at last we got the expression of the relationship. Then we study the mode of bank slump of three loose accumulation slopes, and adopted two methods (STAB and GEOSLOPE Slope Stability Analysis) searching by arc potential slip surface to calculate and analyze, and determined the unstable slip surface of nature and rainstorm state under the normal water level of 2140m and plunged to 2135m water level, so we had get the area of bank slump. At the same time, based on stable slope angle on water and underwater measured in field, we adopted diagrammatical method to predict the area.This study found that, as grain-size changed from coarse to fine, the underwater stable slope angle changed from big to small on different loose accumulation slopes. The grain-size composition and the underwater stable slope angle had definite correlation, and we set up the expression. Based on the expression, we can easily measure the grain size composition to determine the underwater stable slope angle, so that we can quickly predict the area of bank slump by diagrammatical method. In reservoir area, the mode of bank slump on (?)accumulation slope was collapse, and on (?)accumulation and (?)accumulation slope the mode was sliding. We had adopted three methods to predict the area of the reservoir bank slump. At last, we comparatively analysed the three calculations to determine the final area of slump shore.