Deformation Monitoring And Stability Analysis Of The No.12 Landslide Of Panzhihua And Its Posterior Wall

As complicated geological conditions of Panzhihua Airport site, there were landslides occurred in the period of construction at the airport. October third, 2009, large-scale landslides recurred in the east of Panzhihua Airport, namely:"NO.12 landslide of Panzhihua". After the landslide, the landslide has been in a creep deformation. In the rainy season in 2010, the deformation has been getting into a huge acceleration induced by the factors in the rain. And finally, the landslide was occurred again in mid-August 2010. The feature of the NO.12 landslide of Panzhihua deformation was unique, which caused great harm to the safe operation of the airport of Panzhihua. Determining the deformation characteristics and analyzing the steady state of different parts of the landslide by monitoring the landslide deformation, and studying on the deformation mechanism of it have a great significance on Disaster Prevention and Reduction.In this paper, I choose"NO.12 landslide of Panzhihua"as the research object. We studied and analyzed on the landslide, which was based on its geological conditions, soil structure characteristics, and exhibit signs of landslide deformation and the analysis of experimental parameters of physical and mechanical of rock and soil slide. By monitoring the landslide deformation, by analyzing the surface displacement and the deep deformation of the resurrection of the landslide before and after, by using Limit Equilibrium Method and FLAC3D Numerical Method, we analyzed and evaluated the stability of filling the Body High Slope and the edge of the landslide zone of Filling the Body High Slope under various conditions. The evaluation concluded that the Safety Margin of stability of filling the Body High Slope is a little bit low, and the main induction factor of landslide is rain. There are some details and results followed:(1) The students of Chengdu University of Technology have monitored the deep deformation and surface displacement of " NO.12 landslide of Panzhihua " and edge of the landslide body filling high slope, which showed that the natural state of body of the solider area filling has been getting creep deformation at a certain rate. The body of the slider areaâ… -2 andâ… -1 area is the key components of landslide deformation, and they are the first areas to slide. The reason is that the deformation in the front is the result of the pushing in the back. Rainfall is the inducing factor that enhances the rate of lanslide's deformation. In the joint action of various factors eventually led to the decline of the NO.12 landslide of Panzhihua resurrection. As the landslide kinetic energy dissipation and Panzhihua sliding the end of the rainy season, landslides deformation is easing. The monitoring data has verified the landslide as "creep - crack-type" landslide. In the natural state, Body of the Slider Area Filling stays in a smaller strain rate deformation. While deformation rate is a small amount of increased in the rainy season. Monitoring results showed that the steel pipe pile emergency treatment and emergency flood reinforcement works, the stability of the area has improved greatly, but the deep deformation inclinometer monitoring results reveal a potential sliding surface may be developed.(2) Using the limit equilibrium method, the quantitative assessment of the stability of the active landslide slip zone - Fill slider area and the landslide body filling the body trailing edge slope has been evaluated in a natural, storm, earthquake, earthquake, storm and conditions. The results show that: the Safety Margin of Body of the Slider Area Filling is a little bit lower in the natural state, and Filling the Body High Slope can maintain the basic stability; in the storm or earthquake state, Body of the Slider Area Filling may produce large-scale slide area with unstable failure, and Filling the Body High Slope may be in a partial slope failure conditions; while in storm and earthquake state, Body of the Slider Area Filling and the edge of the landslide zone of Filling the Body High Slope, however, a large-scale slope instability and failure will occur.(3) By analyzing the characteristics of Deformation and Stress in conditions of natural state, storm state, and excavation and storm state in the way of Numerical Simulation of FLAC3D, we evaluated the stability statement and compared the Monitoring Results of this situation.