单一突出煤层底板抽放巷优化布置方案研究

为考察单一突出煤层中采用底板瓦斯巷预抽瓦斯的消突效果，在平宝公司矿井单一突出煤层下10m处布置底板抽放巷，分别提出两巷道中心对中心垂直投影距离为0、10、20m以及煤巷外帮对岩巷内帮垂直投影距离为1m等4种钻孔布置方案。结果表明：第3、第4种方案相比第1、第2种方案，每组钻孔钻进距离分别减少20-83、11-74m，施工时间分别减少100-180、80-150min，百米巷道治理周期缩短2-3d，抽放瓦斯体积分数提高10％左右。采用第3、第4种方案后，虽巷道应力分布集中、变形量较大，但通过高强锚网索支护，完全可满足安全生产需要。

Study on Optimized Layout Plans of Floor Gas Drainage Gateway in Single Outburst Seam

In order to investigate the outburst eliminated effect of the gas pre-drainage in the floor gas drainage gateway in a single outburst seam,a floor gas drainage gateway was set at 10 m below the single outburst seam of a mine in Pingbao Company.There were four borehole layout plans proposed,including the center to center vertical projective distance of 0,10 and 20 m between the two gateways,a vertical projective distance of 1 m between the outer wall of the seam gateway and the inner wall of the rock roadway and others.The results showed that in comparison with No.1 and No.2 plans,the drilling distance of each group boreholes for No.3 and No.4 plans could reduce 20~83 m and 11~74 m individually,the construction time of No.3 and No.4 plans could reduce 100~180 min and 80~150 min individually,the maintenance and repair period of the 100 m gateway could reduce 2~3 days and the volume fraction of the gas drainage of No.3 and No.4 plans would be improved by 10%.After the No.3 and No.4 plans applied,though the stress distribution of the gateway would be concentrated and the deformation of the gateway would be high,but with the high strength bolt/steel mesh/anchor support,the gateway could meet the requirements of the mine production and safety.