In order to effectively solve the control problem of a large amount of pressure-relief gas influx to the upper and low-er adjacent seams in the first mining seam of the short-distance thin coal seam group,taking a coal mine as the research ob-ject,the theoretical analysis and numerical simulation methods were used to study the pressure-relieved gas migration law un-der the mining conditions of the short-distance thin coal seam group.The spatial positions of the pressure-relieved gas extrac-tion boreholes were determined based on the enrichment characteristics.The research results show that the maximum develop-ment height of the gas-conducting fracture zone in the overlying strata of the first mining seam is 10.3～23.2 m.The designed super-large diameter bedding pre-drainage borehole is 0.8 m in height and 2.08 m in width.The optimal extraction location of the roof directional long drilling final hole is 15.0～23.0 m vertically from the roof of mining layer and 20.5～27.5 m hori-zontally from the return air roadway.The optimal staggered distance of the buried-pipe extraction is 1.1 m and 1.7 m in height from the floor,and 11.3 m and 20.8 m deep into the goaf.The optimized layout parameters are applied to the field practice,and the gas volume fraction in the upper corner is kept below 0.7％during the mining period of the test working face.The research results can achieve the efficient gas extraction under the conditions of short-distance thin coal seam group,and ensure the safe and efficient production of mines.
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