Study on the Mechanism and Prevention and Control Technology of Strong Mine Pressure in Fully Mechanized Top Coal Caving Mining in Longwanggou Coal Mine

To address the problems of complex mine pressure laws and frequent roof disasters in fully mechanized caving faces with hard roofs, this study takes the 61617 working face of Panel 61 in Longwanggou Coal Mine as the research background, and comprehensively applies methods such as rock mechanics theory, numerical simulation and on−site monitoring to study the manifestation laws and prevention and control technologies of strong mine pressure in fully mechanized caving faces with hard roofs. Firstly, the specific location of the key stratum is determined through theoretical analysis. The UDEC numerical simulation software is used to study the temporal and spatial periodic characteristics of strong mine pressure manifestation, analyze the energy evolution law of the hard roof, and thus put forward the "key stratum energy regulation" hydraulic fracturing roof cutting technology, realizing the whole−process exploration from key stratum identification to energy regulation. The research results show that the coarse sandstone in the 61617 working face is the key stratum. UDEC simulation indicates that the manifestation of strong mine pressure presents significant periodicity, and spatially, the strong mine pressure is concentrated in the area near the working face. The roof energy accumulates in the key stratum, and its sudden release is closely related to the manifestation of strong mine pressure. Based on the energy evolution characteristics of the hard roof, the "key stratum energy regulation" hydraulic fracturing roof cutting scheme is determined. After on−site application, the roadway deformation is reduced by more than 40%, and the support load distribution is more uniform. This scheme can significantly alleviate roadway deformation, optimize the stress state of supports, and reduce the risk of strong mine pressure, providing a promotable theoretical basis and technical scheme for coal mining under similar geological conditions, and is of great significance for promoting the safe and sustainable development of the coal industry.