In view of the problems of large area hanging arch and strong dynamic pressure appearance during collapse of coal seam thick and hard roof during stoping period,which caused difficulties in maintaining adjacent goaf roadways and others,a study on hydraulic fracturing and roof cutting roadway protection technology is conducted.Taking the Hongliu Coal Mine I040201(East)working face as the engineering background,theoretical analysis,FLAC3D numerical simulation and other methods are used to analyze the influence of key parameters of thick and hard roof hydraulic fracturing on the roof cutting and pressure relief effect,and industrial experiments are conducted on the 201 working face.The results show that when the roof cutting angle is 60° and the three layers of rock mass above the roof(coarse grained sandstone,mudstone,and medium grained sandstone)are cut,the concentrated stress borne by the adjacent goaf roadway and protection coal pillar is significantly reduced,and the stress state of the retained roadway is improved.The research results can provide reference for controlling the surrounding rock of the roof under similar conditions.
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