In order to study the range of pressure relief and outburst elimination of the underlying coal seam by the mining of the overlying coal seam with very close distance in the deep part, and to determine the location of the roadway, the No.6 Coal Mine of Pingdingshan Coal Industry Company Limited was taken as the research object. Based on the pressure arch theory and limit equilibrium analysis, the distribution patterns of the pressure-relief and outburst-prevention zones and their interrelationship were theoretically analyzed. Physical similarity simulation tests were conducted to examine the variations in stress and deformation coefficients of the extremely close underlying seam beneath the mined panel, thereby determining the pressure-relief range. Numerical simulations, considering the effect of gas drainage, were performed to study the variation of gas pressure and to delineate the outburst-prevention range. Field measurements of gas content(unit: m3/t) and gas pressure with increasing distance from the mined panel were carried out to comprehensively determine the actual outburst-prevention range. The results indicate that, under the influence of underground gas drainage, the Wu 9-10 seam within 13.95 m of the Wu 8-32030 roadway constitutes the pressure-relief zone, while the area within 30 m constitutes the outburst-prevention zone. The outburst-prevention zone generally lies within the pressure-relief and plastic deformation zones, may extend beyond the pressure-relief range, but does not exceed the limit equilibrium range.
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