The Research And Forecasting On The Mountain River-type Slope Surge Hazard

The damsite of Xiaowan hydropower station is on the border between Lincangarea’s Fengqing country and Dali area’s Nanjian country, which is in the middle ofLancang River. it’s divided into east and west region. Library normal storage levelelevation is about1240meters. It is the key project of Lancang cascade development.In the storage period, frequent changes in water caused reservoir banks recycling,changing the stability of reservoir banks, so that part of the stable slope occurredunstable failure while the individual large-slope caused great damage landslide surge.Because the majority of landslides surge are caused by large and high-speedlandslides,and make enormous threat on the human being and facilities in the dam andreservoir.The water in the reservoir change the topography, lithology, geologicalstructure and weathering and water level changes and other factors. According to thesurvey，there are large loose deposits in the dam, some of them have caused instabilityand large surge, to ensure the safety of the dam and the human being near zhedam.The bank collapse and landslides also will continue occurring.And the researchof the representative landslides surge which have been occurred will be meanful forforecasting the surge which will occur.This article based on extensive field work and the specific field and laboratoryexperiments.By detailed analysising of the engineering geological conditions of thetypical landslide which has been unstable,because the close association between theslope instability and landslide surge. Special analysis the failure mechanism of the typical instability landslide in the library district. By comparing the the existingmeasured data summarize the characteristics of Xiaowan landslide surge andcorrected calculating empirical which calculating the landslide surge of river canyonthat is made by Tianjin Institute of Water Transport Engineering for formula andobtained the formula which is suit for the landslide surge in the Xiaowan reservoir.Combined the results of physical simulation calculation, corrected the calculation ofthe landslide surge in the decay phase.The impact on the curve, the physicalsimulation in this article have been studied, In support of the experimental results,obtained the relationship of bend angle of between surge propagation.On the researchof climbing of the surge,according the estimating and comparing the measured data toget the estimation formula of the surge climbling. And finally through physicalsimulation, further prove that the formula is reasonableBy analyzing the basic geological data of target landslide, and the instabilitymechanism and the evaluation of stability, first, based on numerical calculation of thesliding range, determine the size of the volume of slope instability,then obtain thespeed of the landslide when goes into the water. Then make a reseach by thecalculating by aforementioned surge formula and landslide physics simulation on thesurge propagation characteristics which is in the reservoir area,to achieve goals forforecasting the surge of others typical landslide.