Three-dimensional stability analysis of pingzhuang opencast coal steep slope mining

The boundary of slope angle incline to conservative in Pingzhuang West opencast mine design,resulting in peeling take too much rock and slope toe large backlog of high-quality coal.In this paper,MADIS finite element program was applied for the analysis of west surface mine of steep slope coal area deformation regularity of different excavation width.The results show that the maximum displacement of excavation space along with the increase of excavation length shows first increased sharply,then slowly increasing,then finally reaching the level of flat "S"type growth law,and there is a critical excavation width,so that the point can be defined as two deformation difference obvious deformation stage.Accordingly establishing three-dimensional slope deformation mechanics and based on the limit equilibrium analysis of MSRAMA law of slope stability analysis relationship,the paper puts forward under the mining of steep slope three-dimensional slope stability coefficient calculation method,and draws steep slope mining excavation by steps the law of three-dimensional stability variation and the optimum of excavation width.This new computational method was successfully applied to the slope in Pingzhuang west opencast mine,obtaining a technical,economic,and social benefit.