深孔预裂爆破增透技术在井筒揭煤中的应用研究

汤静+石必明

摘要：为了增加煤层透气性、提高瓦斯抽采率、消除煤层突出危险性，通过数值模拟和现场试验的方法，对深孔预裂爆破煤层增透技术在低透气性高瓦斯煤层中的应用进行了系统研究，得出了煤岩不同的力学性质和控制孔的导向作用。通过对两个爆破孔与控制孔应力云图、裂隙图的数值模拟，再现了应力波在煤岩体中的传播与衰减规律，以及煤岩体裂隙的扩展变化过程。最后，在谢桥矿13-1煤层实施深孔预裂爆破试验，试验表明采用该技术显著增大了煤体透气性，提高了瓦斯抽采浓度和抽采量，故而是一种经济可行的对于防治低透气性高瓦斯煤层突出的方案。

关键词：深孔预裂爆破；低透气性煤层；卸压增透

中图分类号：TD235.33文献标志码：A文章编号：1672-1098（2016）01-0000-00

Abstract： In order to increase the coal seam permeability and the rate of gas extraction， eliminate the outburst， based on the method of theoretical study and numerical simulation， a systematic study of the long borehole pre-splitting blasting applied in the coal seams with low permeability and high gas was carried out. The different mechanical properties of coal and rock mass and the guiding role of the control borehole were obtained. By numerical simulation of stress nephogram and fracture diagram in the area between blasting borehole and control borehole， the propagation and attenuation of stress wave and crack expansion process in coal and rock mass were reconstructed. Finally， the long borehole pre-splitting blasting test was carried out in the 13-1 coal seam of Xieqiao Coal Mine， and the results showed that the permeability of coal seam is increased by using this technology. The concentration and quantity of gas extraction were increased. It is an economical and feasible scheme for the prevention and control of outburst of coal and gas in coal seams with low permeability and high gas.

Key words：long borehole pre-splitting blasting； low permeability coal seam， pressure relief and permeability improvement

近些年我国的瓦斯抽采技术有较快的发展，但是总体水平仍然较低。其中一个重要原因就是绝大多数的高瓦斯和突出矿井所开采的煤层属低透气性煤层，另外随着我国煤炭工业的发展，大多数煤矿已经进入深部开采，煤层瓦斯含量和压力不断增加，煤层透气性不断降低，瓦斯抽采愈加困难。因此，在抽采瓦斯过程中，如何增加煤层透气性已成为亟待解决的技术难题。

近几年来，随着爆破技术，特别是深孔预裂爆破技术的不断完善和发展，使得这项技术在增加煤层透气性、提高瓦斯抽采率、防治煤与瓦斯突出等方面得到了广泛的应用，并取得了良好效果。国内许多学者也对深孔预裂爆破技术进行大量的研究。……