| China is a country with frequent geological disasters,especially in mountainous areas.Landslide debris flow geological disasters often occur,which pose a serious threat to people ’s lives and property.Studying the stability and motion characteristics of landslides has become one of the hotspots in the field of geological disasters.In this thesis,taking a landslide in the mountainous area of southwest Beijing as an example,the natural causes,failure mechanism and debris flow movement characteristics of the landslide are studied by combining the finite element ABAQUS software and the discrete element particle flow software.The main research results are as follows:(1)Based on the survey data and related literature of the landslide in the study area,the geographical location,topography and lithology of the landslide were investigated.Combined with Google historical images,local atmospheric precipitation data and landslide site data,the basic characteristics and causes of the landslide were analyzed.The various factors affecting the formation of landslide in landslide area are summarized,and the influence of topography,lithology and rainfall conditions on landslide is analyzed.The formation and evolution mechanism of landslide is studied,and the disaster process and evolution mode of landslide are analyzed.(2)The influence of rainfall on the reactivation deformation and stability of landslide is analyzed.The finite element ABAQUS software is used to simulate the potential landslide before sliding in the study area under rainfall conditions.Based on the deformation monitoring and analysis of landslide during rainfall,the influence of rainfall infiltration on landslide under fluid solid coupling is considered,and the stability of landslide under different rainfall intensity is analyzed by strength reduction method.The displacement,plastic deformation zone and safety factor of landslide are studied.(3)The discrete element particle flow software is used to simulate the landslide failure deformation and movement accumulation process.The particle flow landslide model is established to monitor the movement time,particle velocity,displacement change and energy evolution process of the landslide,and the characteristics of landslide movement and accumulation are analyzed.(4)According to the existing empirical formula,the velocity of the landslide is calculated and compared with the numerical analysis results.It is concluded that the numerical model landslide velocity is less than the empirical formula method.Comparing the accumulation form of the simulation results with the actual accumulation range,it is considered that the simulation results are basically in line with the actual situation of the landslide. |
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