In response to the problem of large deformation and high instability risk of surrounding rock in the gob-roadway under the lateral thick-hard overhanging roof, this article takes the headgate of the No. 3810 longwall face of Majiliang Coal Mine as the engineering background and investigates the field deformation and failure characteristics. A mechanical model for thick and hard lateral suspended roof was established to determine the reasonable cutting position, which is the distance of coal pillars within 3.98m. A UDEC numerical calculation model was established to invert and analyze the influence of the length and cutting position of the thick- hard overhanging roof on the vertical stress distribution, failure depth, and deformation and failure characteristics of the coal pillar and surrounding rock. The disaster caused by the thick - hard lateral overhanging roof and the pressure relief control mechanism of the roof cutting were revealed. Based on theoretical analysis and simulation results, a hydraulic fracturing for roof cutting technology scheme and its key parameters were proposed and successfully applied in on-site engineering practice. The results show that the maximum deformation of the two sides of the roadway is 600mm, and the maximum subsidence of the roof is 277mm; Compared with the deformation of the roadway in the uncut section, the deformation is reduced by 39.6% (for both sides) and 31.8% (for the roof), effectively reducing the amount of roadway repair work and ensuring safe and efficient coal production.
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