为了解决沙曲矿近距离高瓦斯煤层群开采过程中瓦斯超限这一难题，运用理论分析和数值分析相结合的方法对沙曲矿南翼4号煤开采采动裂隙演化规律进行了分析，确定了高位裂隙钻孔组的合理布置位置。结果表明：采空区垮落带和裂隙带高度分别为8、36.5 m，贯通裂隙带距工作面顶板垂高8~23 m，非贯通裂隙带距工作面顶板垂高23~42 m，工作面上方22 m 左右裂隙分布密集且覆岩整体结构相对稳定，将钻孔延深至该区域能有效提高瓦斯抽采的浓度、抽采量和稳定性。现场实践表明：利用 DDR-1200型千米定向钻机，将钻孔布置在距工作面上方22 m 处时，瓦斯抽采效果明显，平均瓦斯抽采体积分数90.68%，平均瓦斯抽采纯量达11.58 m3/ min。%In order to solve gas content over limit problem occurred in a coal mining process of high gassy and contiguous seams,a theoreti-cal analysis and numerical analysis combined method was applied to analyse the mining cracking evolution law of No.4 seam mining in the south wing of Shaqu Mine and the rational layout of the high level cracking drill hole group was determined.The results showed that a roof falling zone and a cracking zone in the goaf were 8 m and 36.5 m in height individually,there was a vertical height of 8~ 23 m from the cracking zone connected to the roof of coal mining face.There was a vertical height of 23~42 m from a cracking zone no connection to the roof of the coal mining face.The cracks was closely distributed and the complete structure of overburden strata were relative stable in the roof about 22 m above the coal mining face.A drill hole expanded to this region would effectively improve the concentration of the gas drainage,increase the drainage quantity and have a stable gas drainage operation.The site practices showed that with the application of a DDR-1200 mode over 1 000 m directional drilling equipment,drilling holes were made about 22 m above the coal mining face.The gas drainage effect was remarkable,the average concentration of the gas drained was 90.68%,the average pure volume was 11.58 m3 / min.
展开▼
