关键词: 坚硬顶板, 临空巷道, 变形控制, 水力割缝, 顶板爆破

Abstract: There are problems such as high stress concentration, large deformation, and difficulty in support in the goaf under the hard roof. Taking the 21105 working face of Hulusu Coal Mine as the engineering background, the breaking law of the overlying roof during the mining period of the working face under the hard roof is analyzed, the deformation mechanism of the surrounding rock of the goaf is studied, and the control method of "roof drilling and blasting+coal pillar hydraulic cutting" pressure relief in the goaf is proposed, The stress distribution law of the surrounding rock of the goaf roadway before and after pressure relief was simulated using FLAC3D software. After adopting the pressure relief measures of "roof drilling and blasting+coal pillar hydraulic cutting" in the return air roadway of the 21105 working face of Hulusu Coal Mine, the peak stress at the deep base point of the coal pillar decreased by 36.1%, the peak stress at the shallow base point decreased by 19.1%, the daily average energy of microseisms decreased by 67.0%, and the daily total energy of microseisms decreased by 35.7%. Moreover, the occurrence of high-energy events was significantly reduced, and the deformation of the roadway was effectively controlled. The experimental results show that the control technology of "roof drilling and blasting+coal pillar hydraulic cutting" for pressure relief in the goaf roadway can effectively reduce the stress of the coal pillar, reduce the deformation of the roadway, and provide a new governance method for controlling the strong rock pressure behavior of the goaf roadway under the hard roof slab.