大采高工作面采空区覆岩“三带”高度判定研究

Study on Height Judgement of “Three Zones” in Overburden Strata above Goaf of High Cutting Coal Mining Face

为解决大采高工作面采空区瓦斯积聚涌出难题,基于采空区覆岩"三带"对瓦斯涌出量的直接影响,开展对覆岩三带高度确定的研究。综合运用经验公式理论计算、UDEC数值模拟分析及现场实测等方法,对宝马煤矿2301大采高工作面采空区覆岩"三带"高度进行了系统分析。现场实测结果与数值模拟结果相似度较高,而与经验公式计算结果相似度较低。对于2301大采高工作面,采用数值模拟方法来确定其采空区覆岩"三带"高度更为合适。该大采高工作面裂隙带最佳抽采位置为与3号煤层顶板垂直距离为24~30m的区域。

In order to solve gas accumulation and emission problems occurred in the goaf of the high cutting coal mining face,based on the“three zones”in the overburden strata above the goaf directly affected to the gas emission volume,a study was conducted on determination on the height of the“three zones”in the overburden strata.With a comprehensive application of the empirical formula theoretical calculation,UDEC numerical simulation analysis,site measurement and others,a systematic analysis was conducted on the“three zones”height in the overburden strata above the goaf of No.2301 high cutting coal mining face in Baoma Mine.The site measurement results had a high similarity to the numerical simulation results and had a low similarity to the empirical formula calculation results.The numerical simulation method was more suitably applied to determine the height of the“three zones”in the overburden strata above the goaf of No.2301 high cutting coal mining face.The optimum gas drainage location in the cracking zone of the high cutting coal mining face was a area with a vertical distance of 24~30 m to the roof of No.3 seam.