Analysis On Deformation Instability And Comprehensive Assessment On Stability Of Complicated Deposit Slope

Deposit slope is a common landform which is generally located in southwest area of China, and it is usually in a critical state, that even an excavation or rain may lead to crazing, disintegration or landslide, which is harmful to the safty of people and the process of engineering. This research will set a hydropower project engineering deposit slope of left bank before the dam as an engineering example,and analyzes and evaluates the instability of the deposit Slope comprehensively basing on the geological survey, geophysical exploration achievements and deformation control monitoring results to slope deformation. Through the comprehensive analysis and research of a series of changes in supporting the development and process from natural state to the excavation instability of the deposit and to strengthening comprehensive control and so on, finally, summarizes the optimal analysis method of evaluation stabilities. The major research works are as follows:1. It introduces a basic theory and method to analyze slope's stability, and the process or classification of the increasing new theories or new methods for sorting, the paper tried to get a more comprehensive and thorough understanding to the slope deformation failure modes and stability analysis of the theory and method of the complex deposit slope, and to determine appropriate theory and method for analysis for an engineering examples.2. Through the typical profile, deposit parameters and the potential slide crack selection, use a traditional slope stability analysis method for the static equilibrium calculation of the deposit slope, which is called Rigid Body Limited Equilibrium Method, and then work out the safety factor of the slope stability, combine the standard of the safety control of each working condition for stability evaluation analysis before and after the slope excavation.3. On the basis of the engineering geological research and stability comprehensive analysis of the deposit slope, according to the excavation planning, effectively engineering control measures are studied; meanwhile, according to the slope deformation monitoring results, analyzed the characteristics of deformation and summarizes the deformation factors, provide practical basis for the implementation of the comprehensive control measures。4. On the basis of the Rigid Body Limit Equilibrium method, it analyzed the stress, strain and deformation of the research object before and after the slope excavation by using the finite element software PLAXIS2D Numerical Simulation. And then combining the results of the slope stability calculation with the Rigid Body Limit Equilibrium Method for comprehensive evaluation analysis of the deformation instability mode and stability of the deposit slope before and after the excavation, and refine the results for research summary and outlook.The summary of research are as follows: when evaluating and analysing the stability of the slope, the Rigid Body Limit Equilibrium Method and Numerical Simulation Method should be banded together, and after evaluating the results separately, we should give consideration fully to the two methods comparing with their advantages and shortcomings respectively, mutual support and targeting for data and results of the correction. Only in this condition can we get a comprehensive and objective conclusion, and eventually, we can define the instability deformation mode of the complicated deposit slope go for further, and then make effective engineering control measures.