Several rock burst accidents occurred during the excavation of the 4th seam in a mine. Based on the geological and mining conditions of the mine, numerical simulation methods was adopted to analysis the protective effect of the upper and lower protective seam mining on the 4th seam, and the causes of rock burst occurring in the roadway of LW 1410 was explained. Further, the characteristics of stress distribution in 6th seam and 1th seam was discussed, this is the bases for determining the protective effects of upper and lower protective seam mining, as well as the critical pressure relief angle and the critical pressure relief point location in the 4th seam. These parameters would provide meaningful information for optimizing the roadway layout and preventing rock burst in the subsequent face mining of 4th seam.

Aiming at the problem of poor gas extraction, long outburst time and low pre-drainage efficiency in the drilling zone of the floor tunnel through the drilling, the problem of mining excavation replacement is severely restricted. Dingji Coal Mine has carried out ultra-high pressure, medium pressure, and low pressure hydraulic cutting coal seam enhanced permeability gas extraction technology tests. Through continuous exploration and summary, it has achieved remarkable results, maximized extraction, and accumulated rich hydraulic coal Through experience. The results show that: the high-pressure hydraulic coal seam anti-reflection pre-draining unit has a maximum extraction pure volume of 3.1m3/min, the single-hole average extraction pure volume is 0.008m3/min; the medium-pressure hydraulic coal seam anti-reflection pre-extraction unit has a maximum extraction pure volume of 2.2 m3/min, single-hole average extraction pure volume is 0.005m3/min; low-pressure hydraulic coal seam permeability enhancement unit extraction pure volume is maximum 1.3m3/min, single-hole average extraction pure volume is 0.002m3/min. 1351(1)Yunshun’s gas pre-drainage rate reached 65.2% after adopting high-pressure hydraulic coal seam penetration enhancement measures. Through statistical analysis of the anti-burst prediction index during coal tunnel footage, the sensitive index is relatively small, and the effect of pre-draining outburst is better. The lane enters 200m per month. The permeability enhancement technology of hydraulic coal seam has a significant effect on the pre-drainage of gas in high ground pressure outburst coal seam. It provides an effective method for improving the gas pre-drainage and outburst work, which is worthy of in-depth promotion and application.

The high-drainage roadway construction face of the working face is used to pre-drill the borehole under the tunneling face, and the problem of poor water return in the hole is solved by grouting the surrounding rock cracks in the deep and shallow holes of the drill floor. The “two plugs and one note” sealing method was adopted to ensure that the sealing holes were tight and airtight; the water pipes were blown all the way in the hole, and the single hole, grouping and timed water blowing work targets were realized, and the drilling effect of the downhole drilling was improved. A set of efficient and rapid down-drilling and hole-dissipation management mode has been formed, which has achieved the goal of high-efficiency outburst of coal seams and technical and economic integration in areas with high ground pressure and serious safety and economic benefits.

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