Study On SPH Movement Model And Monitoring Method Of Soil Landslide

Landslide is one of the common natural disasters in this world. It reaches more than half of the total case number of all kinds of natural disasters each year. It causes considerable loss of lives and properties due to its destructive power. As one major type of landslides, soil landslide becomes a hard and popular topic among landslide workers. The simulation of the soil landslide movement after its failure, the prediction for the endangered area and the monitoring before its failure are quite important and meaningful for the study of soil landslide. The significance of this work lies in both academic domain and practical project domain.There are two main sorts of work in soil landslide study. The first sort of work is the prediction for the endangered area through high-effient and high-accurate numerical methods and models. The second sort of work is the monitoring work before the landslide slides down. On one hand the analysis of landslide movement and endangered area cannot be done by a experiment performed, so researches in this domain highly rely on the computational assistant technology and appropriate numerical methods and models. On the other hand, a effective monitoring method is the key point to prevent or reduce the losses a landslide can cause. Therefore, based on a deep research on the main numerical methods, models, and monitoring methods about soil landslide, this study summarized the pros and cons of these methods, started from two aspects landslide movement models and monitoring, finally established a set of improved methods and models. The main content is as follows:(1) Based on the smoothed particle hydrodynamics (SPH), this work proposed a three-dimensional SPH model, which was extended from the2D model and constructed on Bimham constitutive relationship. Compared with the2D model,3D model can describe the real state of the practical landslide more vividly. Through the numerical tests and practice landslides tests, it is proved that the3D model is better than the2D model in accuracy.(2) Through correcting the density approximation and the kernel gradient function, the particle approximation precision is improved compared with the traditional SPH method. Considering the complex boundary geometries of landslide, a coupled boundary model is adopted to deal with the boundary treatment without special treatment on the boundary particles. The problem with complex and irregular boundary in landslide model is solved. The stability of the model was improved.(3)The method of establishing the3D particle model in GIS was invented and adopted in the work. It is the important step to apply this SPH model into the soil landslide simulation. Through the numerical tests and practice landslides tests, it is proved that the improved3D model is better than the2D model in accuracy. Also, the3D model was thought to be a suitable method for flow-like soil landslide post-failure movement simulation.(4)Most of the soil landslides exhibit solid movement characteristics instead of fluid. In this study a more accurate mode that is proposed based on elastic-plastic solid constitutive model is used herein with Drucker-Prager yield criterion controlling. It is a more accurate model because the plastic behaviors are considered. Through the enhancement on the method of dealing with the boundary conditions and model construction, we originally applied the method in soil landslide simulation and modeling. The applicability of the model was improved.(5)When it comes to the landslide investigation and analysis, besides the study on landslide movement models, some effective monitoring methods have to be used to analyze the movement characteristics of landslide. In this study, we proposed some monitoring methods based on TLS. After the tests performed in Lab and the result analysis, the error level of this method was evaluated and the standard of the parameter selection in different situations was proposed. We picked the second zone of Jinpingzi Landslide, which is located in Wudongde reservoir area by Jinsha River, as the object of study. With the monitoring work on site and data analysis, it is proved that this monitoring method is feasible. Finally, a fast monitoring system program was developed based on GIS platform, which is meaningful in practical projects.