Research on Gas Outburst Coal Seam Mining Technology Based on the Theory of Gob-Side Entry Retaining

Abstract

Under the condition of traditional mining technology of gas outburst coal seam, the continuous mining of working face is tense, the waste of resources is serious, the amount of roadway excavation is large, and the stress of surrounding rock is large, which results in frequent occurrence of gas outburst, large deformation of surrounding rock, and serious damage to the benefit of coal mine. In this study, a technical method system of gob-side entry retaining, layer-by-layer drainage and pumping roadway without digging rock is put forward. The technology of roof-cutting pressure relief and gob-side entry retaining is adopted to relieve the tension of continuously mining in working face, and to ensure the stability of surrounding rock while improving the recovery rate of resources, so as to provide sufficient time and space for gas drainage along layers in the next section. Gas control roadway instead of rock bottom roadway is used to optimize the layout of mining area and greatly reduce the pressure of roadway working end. Finally, by analyzing the effect of retaining roadway and drainage effect, it is concluded that the average displacement of roof and floor of roadway is 304 mm, the average displacement of two sides is 254 mm, the maximum resistance of support is 44.1 MPa, and the effect of retaining roadway is ideal; the effect of gas drainage is 1.88 times of the original scheme, and 14,989,000 m3 has been drained, and the outburst prevention effect is ideal.