Numerical Simulation Analysis Of Stope Stability About Complex Phosphorus Ore By Chamber And Pillar Method

The mining of gently inclined medium thick ore bodies is a difficult problem in the world.At present,room and pillar method and segmented openstope method at the bottom of the structure are mainly applied in the gently inclined ore body mining.In this paper,basing on a gently inclined medium thick ore body in the west of Hubei,various means are adopted to stope structure parameters to theoretical analysis and checking,such as the literature review,theoretical analysis,the numerical simulation and so on.Based on theoretical analysis,the structural parameters of stope structure are preliminarily determined under the condition of the mining of room and pillar method.Then the finite element software is used to simulate the structure parameters of the stope,so as to prove the rationality of the structure parameters of the stope.These steps provides a reference for the safe,economical and efficient production of the mine.The main research contents and conclusions are as follows:(1)According to the relevant information provided by enterprises,understanding the basic situation of the mining area and summarizing the mining area and the surrounding topography,rock body structure,mining methods and so on are essential.(2)A large number of relevant documentation should be consulted and collected.At the same time,some theoretical knowledge about the mining area deformation and failure mechanism,mode,form and influence factors of stability should be understood and mastered.According to theoretically checking the critical depth of goaf,the failure height and the pillar stability in three aspects,structure parameters of the stope are Preliminary drafted.The more reasonable stope structure parameters have been determined.Namely,to the ph1,the pillar size is 10 m × 10m;The stope width is10m;The spacing of the pillar is 7.5m.To the ph3,the pillar size is 8m × 8m;The stope width is 12m;The spacing of the pillar is 9.5m.(3)According to the structure parameters of stope,the FLAC3 D finite element software is used to simulate the stress and stability of stope under different working conditions.The structure parameters of stope is proved to be logical through the analysis of the stress,displacement and plastic zone distribution and change process.The numerical simulation shows that the results of theoretical calculation are consistent with the mock results,and it is feasible.The parameters of the stope structure can satisfy stability requirements under the condition of safety and high efficiency mining.(4)By means of numerical simulation,the law of ground pressure distribution and sedimentation displacement of the roof and floor are summarized.With the mining of the ore body,the stress release of rock mass on both sides of the mining area is obvious,and the initial stress balance system is destroyed.The displacement of the central position of the roof is the biggest.The farther away from the mining area,the smaller the displacement of rock mass is.Because of the filling body,the stope surfaces vanish and the stress state of stope wall is changed.Under mining conditions,the strength and bearing capacity of the surrounding rock is improved,so that the movement of surrounding rock is restricted,and the deformation is relieved.