Study On The Surge Of Reservoir Bank Landslide And It's Effect On Dam Body

Reservoir bank landslide refers to the ill geological phenomena of reconstruction deformation such as collapse and slippage in reservoir banks under the influence of the reservoir water immersion,storm impact,flow erosion,water level fluctuation and earthquake,which caused by reservoir construction and storage. Not only does the bank landslide block the channel,decrease storage capacity,but also brings adverse effect to the safety of the dam and its downstream region when the waves rise. At present,there have been many examples of great bank landslide hazards at home and abroad,each of which has brought severe endanger and harmful influence. Bank landslide has become a critical problem of hydropower project construction. Different types of bank landslide phenomena or hidden danger exist in most of the formal water storage reservoirs,so aiming at the universal existence of bank landslide in various reservoir projects,it's very necessary to develop relevant researching work. On the basis of summarizing predecessors'experiences and achievements,taking Lechangxia hydro-junction project for researching object,this paper studies on the stability of Egongdai ancient landslide and analyzes the influence of wave surge produced by landslide on the dam. The main achievements include:(1)Analyzing the slip soil shear strength parameters of Egongdai ancient landslide and its stability in various running conditions. Discussing the method of investigating the stability of the ancient landslide with soft sliding surface.(2)Producing the risk degree of Egongdai high-speed landslide and analyzing each degree weighting by using analytic hierarchy process,on basis of which,evaluating the risk degree and providing a new thinking.(3)Putting forward calculation formula improvement and comparing two algorithms calculating landslide acceleration, landslide speed and slip distance aiming at Egongdai ancient landslide on the basis of landslide speed vertical slice techniques raised by Pan Jiazheng.(4)Analyzing and calculating the Egongdai ancient landslide surge by using common landslide surge empirical estimate-method;Constructing 1:150 large scale physical models to research the relation that between the landslide speed and wave surge and that between the water level and wave surge;Raising the influence of volume surge and dam overtopping while calculating the landslide surge through comparative analysis of model test and empirical estimating results.(5)Testing the surge pressure of Egongdai landslide surge in front of the Lechangxia reservoir dam,raising surge pressure calculating model. Evaluating the dam security under the surge effect through the surge pressure calculating model.(6)Analyzing and summarizing bank landslide preventive and controlling principle,thought and method. Comparing reinforcement scheme of Egongdai ancient landslide between anti-slide pile and filling earth counter pressure.