Research on reasonable width of protective layer coal pillars on prominent coal seam groups
The mining of the upper protective layer is one of the effective technical measures for preventing and controlling coal and gas outbursts in the underlying coal rock mass of coal seam group mines.In order to study and determine the reasonable width of the coal pillars left in the working face of the upper protective layer,based on the engineering background of the upper protective layer of the lower3 thin coal seam in the No.21 mining area of a mine in northern Shaanxi,the stability of the coal pillars left in the protective layer and the pressure relief and permeability enhancement effect on the underlying coal rock were studied.Through a combination of theoreti-cal analysis and numerical simulation,the reasonable width of the coal pillars left in the lower3 thin coal seam protective layer was opti-mized and determined to be 15-20 m,taking into account factors related to mine safety production and economic benefits.
万方数据
维普
