Key Technologies Of 3D Dynamic Visualization Of Landslide Process

On account of difficulty to predict,great destructivity and short acting time,Landslide invariably causes enormous threats and damage to people’s life and property in the disaster area.To construct the 3D geographical scene of landslide disaster area based on multi-source and multi-temporal remote sensing data,and to simulate the evolution process of the disaster with a 3D dynamic visualization method,can be conducive to restore the process of disaster occurrence,obtain disaster information,analyze damage degree,and can also provide scientific basis for further emergency treatment,post disaster rescue and reconstruction.Pointing at the deficiencies and disadvantages of realism lacking and low efficiency when rendering in existing researches with regard to 3D dynamic visualization method of landslide process,a 3D dynamic visalization prototype system for simulation of landslide,which is focusing on realistic and efficient expression,is designed and implemented in this paper by exploring the calculation of transient 3D model of landslide mass and researching the efficient scheduling of models and rendering of scene.Following four research contents and achievements are mainly included in this paper:(1)This paper analyzes the defects and shortcomings of mesh method and mesh-free mothod in the numerical calculation of landslide movement.Combined with the theoretical system of the fluidization of landslide process,the particle-in-cell method is proposed as the numerical calculation method,and the time-space process simulation of landslide movement considering the physical characteristics is realized by constructing the triangle mesh model for the numerical results.(2)Based on multi-source and multi-temporal remote sensing data,the basic geographical feature information of landslide disaster is extracted,including the scope of landslide mass and the coverage of geological body after landslide.A technology of building initial 3D model of landslide and sliding surface based on these remote sensing data and landslide disaster feature information is proposed.(3)3D dynamic visualization of landslide process with high reality and high efficiency is realized by proposing the technology of virtual 3D geographical scene based on the terrain data and image data of the disaster area and implementing the efficient scheduling stategy of 3D models of landslide mass with high-dynamic time sequency.(4)A prototype of 3D transient model calculation and a prototype of 3D dynamic visualization for landslide process are implemented,and a large landslide occurred in Xinmo Village,Maoxian County,Sichuan Province on June 24,2017 is selected for experimental analysis.Experiments show that the 3D dynamic visualization system of landslide disaster designed and implemented in this paper can well realize the dynamic display of landslide process.Compared with the existing methods and systems,it has the characteristics of more realistic expression of landslide process,more efficient model scheduling and scene rendering.