软、硬分层煤体瓦斯含量在同一穿层钻孔的差异性研究OA

Gas content is one of the important indicators for regional prediction and evaluation of extraction standards.There are certain differences in the adsorption,desorption,and diffusion laws of gas between soft and hard coal,and the"Detailed Rules for Prevention and Control of Coal and Gas Outburst"stipulate that the critical value of gas content should not exceed 8 m3/t and that boreholes with outburst hazards should be arranged in soft layers as much as possible.In order to further study the differences in gas content between soft and hard coal bodies in the same drilling through layers,an analysis and research were conducted using the Jiaozuo mining area as the engineering background.Research has found that there is little difference in gas content between soft and hard layered coal in the same borehole,whether it is the original coal body or the depressurized and enhanced permeability coal body.When conducting the ef-fectiveness test of regional measures,multiple sampling points are arranged for each borehole,and only the area controlled by the sam-pling points needs to be considered,without considering the location of soft and hard layers.