Research On Coal Pillar Size Optimization And Surrounding Rock Control Of Roadway Driving Along Goaf In Fully Mechanized Caving Face

The stability of surrounding rock of gob side entry driving in fully mechanized top coal caving face is the focus of rock mechanics and mining academia at home and abroad.Taking the gob side entry of 204 fully mechanized caving face in Gaojiapu coal mine as the engineering background,the deformation and failure mechanism,size optimization and surrounding rock control measures of roadway driving along goaf are deeply and systematically studied in this paper.It is of great significance for reducing coal loss,reducing roadway support cost,improving economic benefits and ensuring mine safety in fully mechanized caving face of Binchang mining area The safe mining of working face has certain reference significance and engineering practical value.In this paper,by means of theoretical analysis,numerical simulation and field measurement,the deformation and failure mechanism of coal pillar in gob side entry driving is analyzed,and the mechanical characteristics and deformation characteristics of coal pillar in gob side entry driving are deeply discussed,and the mechanical model of coal pillar driving ilong goaf is established,and the reasonable range of coal pillar parameters in 204 working face is determined.On this basis,FLAC3D software is used to analyze the distribution law of stress field and displacement field of coal pillar with different width under the condition of 4m?30m by using FLAC3D software.From the perspective of mine pressure prevention,the coal pillar size of gob side entry driving in deep fully mechanized caving face is optimized.The critical parameters of small coal pillar are tested by surrounding rock loose circle test,coal stress monitoring and multi-point displacement monitoring.At the same time,based on the analysis of the maximum resistarice of the surrounding rock and the supporting effect of the bolt along the gob,the paper puts forward the optimization scheme of the support along the goaf.This study not only provides a solution for the safety production of Gaojiapu coal mine,but also provides theoretical basis and engineering reference value for the optimization of coal pillar size and surrounding rock control of roadway driving along goaf under strong dynamic pressure in similar mines.