Study On Stability Of Anti-dumping Layered Slope-

Destruction of anti-dumping slope structure is a typical form of rock slope deformation instability, the anti-dumping layered slope deformation and failure of performance: occurrence of layered rock mass are obviously slowing down, dislocation occurs between rock, loosening or even destroy the entire rock, which occurred "nod" phenomenon. This paper to Ciha Gorge Hydropower Station right bank No. II dumping body as the research object, through field investigation engineering geological conditions in the research area of No. II, dumping dumping deformation failure mechanism analysis, and using finite element numerical simulation method to study No. II toppling deformation body under six conditions of stability.The main methods and the main recognition of this paper are as follows:1. The No. II dumping body in which the region’s topography, lithology, regional tectonics, neotectonics and earthquakes, hydro-geological conditions, geological conditions are described in detail, and the No. II dumping of engineering geological condition and the deformation characteristic is described in detail, and analysis the deformation failure mechanism.2. According to the deformation character of the field geology survey data and No. II dumping body can analysis the deformation failure mode and mechanism which is belong to the deformation and failure mechanism of the composite. The initial deformation mainly for reverse steep inclined rock bend, crack, then converted to creep ~ tension type failure mode, and so deformed to a certain extent, by the toppling toppling eventually transformed into landslide, landslide way to end The deformation process. At present, the development of dumping body has formed a potential break, and is in the creep deformation and cracking stage. From the process of geological history, it is in the transitional stage from the deformation to the unstable failure.3. A representative cross-section on the No. II dumping body is selected, using the finite element software to carry on the simulation, by finite element software Phase2 analysis the stress distribution and slope stability under the four conditions: natural condition, earthquake, excavation condition, seismic + excavation. and then use finite element software GeoStudio analysis No. II dumping effect in stability under two kinds of conditions : in rain and fog, rain and fog + excavation. The results of simulation show that the stability coefficient is as follows: under the natural state of stability is 2.03. Under the action of earthquake is 1.1, under the excavation conditions of stability is 1.3, rain and fog(10day) effects of stability is 2.41, under the condition of rain and fog effects and excavation(10day) of stability is 2.359, under the condition of earthquake and excavation of stability is 1.21, under the above conditions, No. II dumping body stability coefficient was greater than 1, so it is in a steady state.4. The simulation results show that, the earthquake and excavation of these two conditions have a greater impact on the stability of No. II dumping body, therefore, it is suggested that of No. II dumping body of slope reinforcement(such as bolt, cable) so as to enhance its stability. After the excavation the underground water level changes in the larger in the long time of fog(10day). and the slope stability is extremely unfavorable, it is recommended slope after excavation should build proper drainage system(such as drainage ditches, Drainage holes, etc.).