The Three Dimensional Visualization And Dynamic Simulation Of Landslide In Three Gorges Area

The landslides cause huge casualties and property losses worldwide everyyear. The complex geological conditions and changing weather conditions in theThree Gorges reservoir area provide chances of large numbers of landslideoccurrences. Therefore, there is significant importance to determine the scope ofthe landslide hazard and simulate the landslides process. This paper selects atypical landslide in Fuling District, simulates the landslide hazards range usingthe Sassa’s landslide movement model, and performs a dynamic simulation oflandslide process based on the results of the Sassa’s model. The research work isdetailed as follows:(1)This study determines the research idea and method of landslide hazardareas and the dynamic simulation process based on a review of literature onthree aspects, namely landslide research, visualization techniques, landslidemotion model and dynamic simulation.(2) This study creates the digital terrain model and draws athree-dimensional landslide model based on the landslide basis terrain data andusing four interpolation method, bilinear interpolation, nearest neighborinterpolation, cubic spline interpolation and bicubic interpolation. It thensimulates the landslide slip surface using anti-distance interpolation and Kriginginterpolation according to the drill points and landslide hazard area contourpoints.(3) This study analyzes the basic assumptions of the Sassa’s landslidemotion model and the block landslide motion model. The Sassa’s landslidemotion model is selected as a computational model according to thecharacteristics of the landslide model, and the numerical calculation of thelandslide movement is done by using the finite difference method, the resultgive the displacement, velocity and range of the landslide.(4) A gray-scale map is generated that can be used as a replacementmodeling using GIS tools and Photoshop.(5) This study also builds the landslide terrain model using terrain toolsand displacement maps. The advantages and disadvantages of the two models are analyzed, and a displacement map model as landslide model is selected.Based on the position of the sliding surface, the sliding block and landslide-bedmodel is generated using Boolean operations.(6) Lastly, this study carries out dynamic simulation of the landslidemovement with a particle system. In the simulation, the influence of thephysical collision of the sliding block and landslide-bed is considered, andtexture and smoke are added in order to achieve a better effect.To sum up, this study determines the position, velocity and range of thelandslide and simulates the landslide process according to the topographic dataand soil parameters. The results of this study have a great significance on theearly warning and disaster assessment of landslide in the Three Gorges reservoirarea.