3D Modeling Of Landslide Based On UAV Aerial Photography And Risk Rssessment Research

Landslide is a highly destructive geological disaster in which the stable shape and structure of a mountain body is changed and destroyed under the action of the gravity of the rock and soil itself or by external forces.It has the characteristics of randomness,suddenness,and serious losses.Life and property,transportation safety,and social and economic production organizations pose great threats.Therefore,the research on landslides has important social value and economic significance.Due to the suddenness of landslide disasters and the difficulty of field surveys,it is urgent to respond to emergency disasters with a rapid emergency response,strong flexibility,and high precision surveying and mapping technology.Based on this background,this article uses drones as a flying platform,equipped with multi-lens aerial cameras,and builds an oblique photogrammetry system to collect data from different angles such as vertical and side views.The research is based on the production of real-life 3D models in Maqu County.The object is based on the Context Capture software system,combined with the results of image control points,UAV POS data,and original images to realize fully automatic 3D modeling of real scenes,and conduct quality evaluation and analysis of model results to verify the operability of the method.Then take two typical landslide areas as the research object,make high-precision DEM,DOM,DSM and other products,so as to conduct landslide risk assessment.Based on the analysis function of Arc GIS,analyze the slope,aspect and section of Zhouqu County,combined with the strength value,comprehensively judge the scale and hazard of the landslide,carry out the regional landslide risk assessment,and finally establish the landslide post-disaster database based on Arccatalog,and analyze the landslide area Data is managed efficiently and orderly.The main findings of this paper are as follows:(1)Based on the model produced by the UAV data processing software Context Capture,its data collection and processing process is more flexible and simplified,with higher simulation accuracy,and can meet the actual needs of emergency treatment of landslide disasters.This method has certain feasibility in the whole process monitoring application of landslide disaster.(2)This paper selects the landslide(landslide body A)on the south side of the river course in Nanyu Township,Zhouqu,and the landslide on the north side of the river course(landslide body B).The slope,slope surface,slope direction,And the comprehensive analysis of the strength value can well evaluate the disaster intensity level.The comprehensive analysis shows that the landslide body A belongs to the landslide below the medium scale,the disaster-causing intensity is below the medium scale,and the landslide body B belongs to the larger-scale landslide.The intensity of the disaster is great.(3)Seven influencing factors including slope,aspect,elevation,rainfall,vegetation coverage,river distance and road distance are selected,and the weight of each influencing factor is determined by the analytic hierarchy process,and the risk assessment of landslides in various towns in Zhouqu County is carried out.From the analysis of the results,slope is the most important factor affecting landslides in Zhouqu County.Nanyu Township is in a high-risk area of landslides,and secondary landslides are very likely to occur and must be managed.(4)After sorting out the vector data and raster data of Zhouqu County,the landslide database of Zhouqu County Based on Arc Catalog can provide detailed and reliable data support for post disaster landslide clearance,urban reconstruction planning,and early warning of surrounding dangerous areas.