腾晖煤业采空区顶板超长定向钻孔模拟与应用研究

基于采动裂隙椭抛带理论提出顶板超长定向钻孔治理技术，通过理论推导、数值模拟、现场应用相结合的方法对腾晖煤业2-100放顶煤工作面顶板超长定向钻孔的合理距离及合理层位进行研究。研究结果表明:1~5号顶板超长定向钻孔内错回风巷的合理距离为20~40 m；钻孔的合理终孔层位依次为60,60,60,61和63 m。顶板初次垮落后，顶板超长定向钻孔开始发挥作用，单孔的瓦斯抽采纯量随着工作面推进开始呈周期性变化，当顶板岩层发生周期性垮落时，钻孔瓦斯抽采纯量开始急剧升高；抽采纯量达到的最大值分别为13.88 ，13.92 ，13.96，14.24 和14.32 m3/min；顶板超长定向钻孔抽采期间，上隅角瓦斯浓度与回风流瓦斯浓度呈周期性变化趋势，上隅角瓦斯浓度为0.32%~0.8%，整个过程中上隅角瓦斯浓度均在可控范围内。顶板超长定向钻孔治理技术可有效解决放顶煤工作面采空区的瓦斯治理难题。

Study on simulation and application of roof super long directional borehole in goaf of Tenghui coal industry

The control technology of roof super long directional borehole was put forward based on the theory of mining fissure elliptic paraboloid zone, and the reasonable distance and horizon of the roof super long directional borehole in the 2-100 top caving coal face of Tenghui coal industry were studied through the combined method of theoretical derivation, numerical simulation and field application. The results showed that the reasonable distance for the internal staggered return airway of the No. 1 to No. 5 roof super long directional borehole was 20-40 m, and the reasonable end borehole horizon was 60 m, 60 m, 60 m, 61 m and 63 m in turn. After the first collapse of the roof, the roof super long directional borehole began to play its role, and the pure drainage quantity of gas with single hole started to present the periodical change with the advancement of working face. When the roof strata occurred the periodical collapse, the pure drainage quantity of borehole gas began to rise sharply, and the maximum value of pure drainage quantity was 13.88 m3/min, 13.92 m3/min, 13.96 m3/min, 14.24 m3/min and 14.32 m3/min, respectively. The gas concentration at the upper corner and the gas concentration of return air flow showed a periodic change trend during the drainage process of roof super long directional borehole, and the gas concentration at the upper corner was 0.32%-0.8%, which was in the controlled range during the whole process. The control technology of roof super long directional borehole can effectively solve the difficult problem of gas control in the goaf of top caving coal face.