红菱煤矿开采保护层对煤岩体透气性的数值模拟

Numerical Simulation on Air Permeability of Mining Protection Layer in Hongling Coal Mine

以红菱煤矿保护层开采为工程实例,通过开采11#煤层,对存在煤与瓦斯突出的7#煤层和12#煤层进行卸压,利用FLAC3D数值模拟中小同步开挖的渗透率变化情况,对保护层开采过程中煤岩体的渗透性进行了分析,得出了煤岩体透气性变化规律。结果表明:煤岩体的透气性随着工作面推进不断增强;开采保护层上覆岩体的渗透率明显比底板岩体的渗透率大;卸压效果越好,渗透率越大。

The depressuring of No. 7 and No. 12 coal seams with outburst of coal and gas through mining No. 11 coal seam of Hongling Coal Mine in Shenyang was tested, the simulating of the variation of permeability with excavating was carried out by FLAC3D, the air permeability of coal during the mining of protection layer was studied. The result indicates that the air permeability of coal is continually strengthened as working surface impels, the permeability of overlying rock mass is obviously larger than that in underlying rock mass, and the more perfect of the pressure release is, the bigger the permeability is.