关键词: 近距离煤层, 水力压裂, 悬顶效应, 围岩支护, 切顶卸压

Abstract: For the bottom pumping road of close-distance coal seam, it is in a high stress state after the upper working face mining and it is difficult to maintain. The hydraulic fracturing technology is studied. It is concluded that the hard roof of the hard surface is easy to form a long time span. The overhanging effect is the key to the pressure of the bottom coal roadway. Hydraulic fracturing eliminates or weakens the formation of hard roof and improves the overburden of the goaf. The proportion of stress distribution in the coal pillar is changed and the stress state of the bottom pumping road is improved; The multi-stage retracting hydraulic fracturing technology combined with the straddle drilling packer forms obvious artificial cracks in the hard rock strata of the roof, which reduces the stress concentration of the surrounding rock of the bottom pumping roadway and reduces the maintenance difficulty of the bottom pumping roadway.