Strong mine pressure appearing mechanism and control at deep buried working face with large mining height

During the mining of the adjacent working face, the strong mine pressure caused by the hard thick roof has obvious zoning characteristics due to the mining of the previous deeply buried large mining height working face. The mechanism of the strong mine pressure at the adjacent working face is the basis for realizing safe and efficient mining. This paper takes the deeply buried large mining height working face at Huangling No.2 Mine as the background, and adopts the methods of geological investigation, theoretical analysis and numerical calculation to analyze the characteristics of the strong mine pressure, the breaking characteristics of the hard thick roof, and the evolution relationship between energy and stress, so as to reveal the occurrence mechanism of strong mine pressure at the adjacent working face of the deep-buried large mining height, and specifies the prevention and control direction of the strong mine pressure. The results show that the number and energy of microseismic events generated by the hard thick roof accounted for 52.12% and 69.4% of the total number of events and total energy, respectively. Zoning display feature was formed in which the value of the energy release on the proximal side was large, and the interior of the roof plate on the solid side was basically intact along the tendency of the working face. The hard thick roof plate constraint boundary conditions of “two solid support, one simple and one free” breaks at the working face tends to be about 108m from the coal pillar of the adjacent section of the breakage. The energy and stress of the hard thick roof under the mining disturbance of 21422 working face form a reduced distribution characteristics from the airside to the solid side. The zonality of the stress and energy distribution is consistently related to the asymmetric breaking of the roof, as derived from the concentration difference coefficient. The hard thick roof has a high degree of release in the 110m range on the air side, and is in a energy storage stage in the range of about 70m from the coal pillar on the boundary of the solid side. According to the results, the strategy of weakening the stress concentration of the roof plate on the airside and blocking the transmission of stress on the solid side has been formed, which provides a reference basis for the effective prevention and control of the strong mine pressure in the deeply buried large mining height working face.