Stability Analysis Of Coal Gangue Dumping Site Slope In One Of The Pingdingshan Coal Mines

The coal gangue dumping site slope is mainly deposited by coal gangue and stony soil, and its stability condition seriously affect the mine's production and safety. As a number of this type slopes occurred failure and caused huge loss of lives and property in recent years, it's necessary that carry out the slopes stability analysis and evaluation work. This thesis studied the slope in one of Pingdingshan coal mines, and separately using the 2-D limited equilibrium method and finite-difference strength-reduction method calculated and evaluated the slope stability. Finally it compared and analysed the two methods results. The search results are as follows.1. In limited equilibrium method, the problems of solving safty factor in Fellenius method ,simple Bishop method and Spencer method has been discussed. Considering the features of the slope, the improved decimal strings genetic algorithm method was emplyed to search the circular critical slip surface of the slope. Moreover, based on Delphi 7.0 platform, the 2-D slope stability calculation program-SCG with Fellenius method ,simple Bishop method and Spencer method was programmed. Then the SCG program was tested and analysized with the standard slope example and Slide program.2. The criterions of slope failure in finite-difference strength-reduction method has been studied. The stability of standard slope example was calculated with the FLAC program. Then, the result was compared with the answer of the example with simple Bishop method. Finally, the slope parameters'effecting upon the safty factor was discussed.3. Through analysing the geological conditions of the studied slope, the thesis proposed a possible failure mode, and separately used SCG program and FLAC program to calculate the slope stability. Then there is a discussion about the differences between the results calculated by Fellenius method, simple Bishop method and Spencer method. Afterwards there came a comparison between the results of SCG program and FLAC program.4. Combining the results of limited equilibrium method with the ones of finite-difference strength-reduction method, an evaluation on the slope's stability was proposed according to responding codes. A conclusion could be drawn that except the carrying side, the other three sides are unstable in the condition of rainstorm. Besides, the stack gradient and height have a large effect on the slope stability. In the end, the thesis suggested some comprehensive control measures of the slope geological environment.