大采长工作面以孔代巷瓦斯治理技术研究

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中图分类号：TD712.6 文献标志码：A

Abstract：At present，most studieson the borehole layout parameters in thegas drainage technologyof replacing roadwaywith borehole determine the borehole heightonlybasedon the "three-zone"distribution，while there is litte research on the horizontal positionand spacing of boreholes.To address this problem，taking Pingmei15o50 working faceas theengineering background，the layout parametersofdirectionallong boreholes in theroofofa large mining height working face were determined by combining physical similarity simulation experiments，theoretical analysis，and numerical simulation.Physical similarity simulation experimentswere establishedinboththestrikeanddipdirectionsofthe1505Oworkingface.Thecharacteristicsofoverburden collapse in strike and dip directions of the large mining height working face were analyzed.The height of the caving zone was found to be 11.5m ，and the height of the fracture Zone was .The gas enrichment areas in the goaf were determined as the fracture Zones near the return airway and the working face，which indicated the direction forthedrilling locationsof directional long boreholes.Toaccurately calculate the horizontal positionofthe corresponding boreholes，acalculation model forthehorizontal positionof directional long boreholes was established basedon theresultsof physical similarity simulation inthe dipdirection，and a formula for calculating the horizontal position of boreholes was derived.In order to determine the reasonable spacing of boreholes，a gas drainage model for the roof directional long boreholes was established，and the gas flow direction and concentration distribution were simulated under conditions without long boreholes and with different borehole spacings. The reasonable spacing of boreholes was determined to be 5m in the vertical direction and 3m in the horizontal direction. Field application results showed that the average gas volume fraction was 16.1% ，the average net drainage volume was 4.1m3/min ，and the average gas volume fraction in the upper corner was 0.43% ， achieving the expected effect of gas control in the working face by replacing roadway with borehole.

Key words： large mining height working face; directional long borehole;overburden collapse；borehole parameters; fracture zone; caving zone; gas enrichment area; replacing roadway with borehol

0引言

回采工作面采空区瓦斯高效抽采是解决上隅角瓦斯浓度超限的关键所在。（剩余10427字）