Study On The Influencing Factors Of Surge Height Of Rock Landslide

Hydrodynamic landslide is a kind of slope rock and soil instability disaster driven by rainfall,glacial snow melting,water level change,surface runoff and groundwater activity.In the reservoir area of water conservancy and hydropower projects,hydrodynamic landslides often occur under the influence of water level changes such as water storage,flood discharge and heavy rainfall.One of the secondary geological disasters is landslide surge,which mostly occurs in the reservoir area.As the reservoir area is a water conservancy project,there are dams,hydropower plants and other hydraulic structures in its downstream.Once there is a landslide surge,not only will the economic benefits of the reservoir area suffer great losses,but also will affect the safety of shipping and related hydraulic structures,and sometimes even threaten the life and property safety of the people around the reservoir area.The research content of this paper is mainly to study the law of the height of the surge under the action of various factors,the maximum wave height of the landslide surge and the wave height in the upstream and downstream propagation process of the river channel in the reservoir area.Firstly,this paper selects and determines several main factors affecting the surge height by reading the literature,including the length,width,thickness,inflow speed,sliding surface angle,water depth,river of the landslide mass The study of the influence on wave height can provide basis for disaster reduction and prevention.In order to explore the influence of various factors on the maximum wave height,the specific research contents of this paper are as follows:(1)Select a typical landslide surge accident as the prototype,use FLOW-3D software to simulate the process of landslide into water,calculate the surge height,and explore the influence characteristics of various factors on the landslide surge height by changing the characteristic factors of landslide mass and river channel,and finally analyze the results of logarithmic value simulation,define the maximum wave height from the perspective of disaster.(2)Taking the same landslide surge project as the prototype,the physical model experiment is carried out.According to a certain proportion of different types of landslides,the process of landslide surge into water,the formation process of landslide surge,the propagation and attenuation process of surge are reproduced.The numerical simulation is compared;the wave height caused by different types of landslides is also explored,combined with the experimental data analysis of its impact on the surge wave height,to provide a basis for disaster prevention and mitigation.(3)The study on the influence of various factors on the wave height means to provide basis for disaster prevention and mitigation.According to the research law and geological survey,the general scope and wave height of the landslide can be predicted,and the small wave height can be reduced through certain human measures.According to the above research contents,the research results are as follows:(1)With the increase of each factor,the corresponding maximum wave height will increase in varying degrees,and regression of each factor to the maximum wave height fitting formula,sensitivity analysis,sensitivity coefficient from large to small in order: sliding surface angle,length,thickness,width,water speed.It can be seen that the influence of various factors on wave height is different.(2)With the increase of water depth,the corresponding wave height of landslide surge decreases.With the increase of channel width,the corresponding maximum wave height will decrease.According to the numerical simulation analysis,the maximum wave height is defined.The place where the maximum wave height occurs is in the near range of the landslide body entering the water,generally occurs in the semicircle with the stop point of the landslide body entering the water as the center,and the direction is vertical upward.(3)The landslide mass is divided into the whole and the discrete.The results show that the maximum wave height aroused by the whole type of sliding block is generally higher than that of the discrete type,and the wave height aroused by the whole type of sliding block is generally lower than that of the discrete type.(4)The measures for disaster prevention and mitigation are put forward,which are the function of arranging fiber net to pray for obstruction in the sliding process of landslide,and the energy dissipation effect of wave reducing plate and reducing wave propagation energy to achieve the purpose of disaster reduction.The results of this study will be able to predict the height of the landslide surge,which is of great significance for the safety assessment of the reservoir area and provides reliable support for the protection of people's property and life safety in the reservoir area,and has practical engineering application value.