Stability Analysis And Recovery Sequence Optimization Of Horizontal Pillars Under Tectonic Stress

Based on 2 area in jinchuan mine 2 # ore body of 1000 m in the middle level pillar as engineering background.By adopting spot investigation,the technical means of theoretical analysis and numerical simulation to analyze the stability of level pillar status,on the basis of the stability of level pillar stoping sequence optimization research to its,in this paper,the main research contents and conclusions are as follows:1,the theory research.Level pillar was simplified,the article use elastic foundation theory and catastrophe theory to the study.first,level pillar is simplified as elastic foundation beam,by minimum potential energy with the virtual displacement principle and Liz method integrated use of,is used to approximate the deflection of level pillar.Then on the basis of the level pillar mutation model is established,using the cusp catastrophe theory to establish mechanical model,it is concluded that necessary and sufficient condition of its instability.2,using FLAC^3D numerical model,the analysis from the aspects of displacement,stress and plastic zone of the accumulation of ore body stoping and lower ore body stoping to level pillar mechanics effect,result show that the horizontal pillar can adjust footwall of surrounding rock stress distribution in the local scope,mining activities will not pose a threat to global stability;With the pillar being thinning,wall damaged zone of surrounding rock increases obviously,this is the significant discriminant pillar stability judgement standard,footwall rock mass monitoring should be strengthened.3,Level pillar stoping sequence is optimized,the article comprehensive analysis of the four kinds of scheme after extraction of displacement,stress and plastic zone and other mechanical properties,it is concluded that the optimal recovery plan for the two wings to the middle of stoping sequence,the research results provide the theoretical basis for pillar stoping.And four kinds of mining sequences and ore pillar recovery after Bi were induced by mining goaf footwall adjacent rock large deformation and failure,this mainly concerns with the corresponding pillar orebody footwall space form,the need to cause enough attention.4,The preliminary monitoring system.According to the actual situation of mine,combined with the numerical simulation results,using the displacement and stress associated with acoustic emission monitoring method,the mine ground pressure monitoring in jinchuan mining area 2 level pillar.