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Abstract The direct roof of coal seam in a Mine is hard limestone, and the compressive strength can reach 120 MPa. In order to improve the recovery rate of coal resources, the research on directional pre-splitting blasting roof cutting and pressure relief roadway retaining technology was carried out in No.21902 Face. The structural model and mechanical model of the short arm beam were established, and the principle of roof cutting was analyzed. By artificially forming slits in the roof strata, the transmission of force between the goaf and the upper part of the roadway could be reduced. On this basis, the roadway retaining technology of advance reinforcement + blasting roof cutting + unit support based on constant resistance anchor cable was proposed, and the supporting parameters of different mine pressure areas were determined. The U29 steel retractable pillar and polyurethane material were used to spray and seal the goaf. Field observation showed that the deformation of roadway was small, and good effect of retaining roadway was achieved.
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