Mining technology of contiguous coal seams influenced by room-pillar goaf

GAO Chao; HUO Junpeng; DENG Weinan; LU Shaoshuai

doi:10.11799/ce202312008

Abstract：In order to safely mine the shallow contiguous coal seams affected by the room-pillar goaf,based on the geological and mining conditions of 2-2 coal seam using room-pillar mining method in third panel,Hanjiawan Coal Mine,using integrated detection technique of"goaf drilling+leakage observation+goaf water detection+dimensional laser scanning",it is obtained that roof crack development degree of the room-pillar goaf is low,roof strata are relatively complete,the parameters of coal pillar and warehouse are 7 m and 8 m,respectively;and the height of goaf water in some areas is 0.15～0.35 m.Based on laboratory test results,stability of residual coal pillar under the current condition of 2-2 coal and the stability of disturbed 2-2 coal pillar under the over-goaf mining of 1-2 coal longwall working face are calculated and analyzed by relevant theories.Results show that residual coal pillars of different room and pillar mining sizes of coal 2-2 are temporarily stable under the current situation.The abutment pressure of 1-2 coal longwall face mining over 2-2 coal room pillar goaf affects 2-2 coal residual pillar can not keep stable;the mining scheme of"mining group coal seam first,using mine pressure to destroy the residual coal pillars of coal 2-2,and then implementing the house-pillar type goaf after the upper group coal push off disturbance destruction"is technically feasible.