中文摘要：

为研究深孔定向聚能爆破的裂缝特征及应力演化特征，搭建定向聚能爆破试验系统，开展定向聚能爆破试验，分析聚能方向和非聚能方向的裂缝特征、应力演化规律。试验结果表明，定向聚能爆破的爆炸能量主要集中在聚能方向，能够在聚能方向侵彻煤体形成较大的裂缝，产生的裂缝长度远大于非聚能方向；定向爆破的聚能效应导致试样的应力状态在聚能方向发生显著变化，聚能方向的力学变化大于非聚能方向。同时，进行深孔定向聚能爆破的现场试验，煤层采用定向聚能爆破增透技术后，瓦斯抽采量增大10～40倍，有效抽采半径达到7 m，并且定向聚能爆破对煤层顶底板的破坏较小，较好地保护巷道围岩的完整性。研究成果对井下煤层实施定向聚能爆破治理瓦斯灾害有重要的科学意义和应用价值。

英文摘要：

In order to study the crack and stress evolutions caused by the directional focused energy blasting in deep borehole,an experiment system was constructed,and a series of laboratory and field experiments together with the field experiments of directional focused energy blasting were carried out. The results show that the energy of directional blasting mainly concentrated in focusing direction and then penetrated the coal sample with the cracks in focusing direction much longer than those in other directions. Because of the effect of directional focused energy blasting,the mechanical properties of the samples in focusing direction were changed much more significantly than in other directions. The permeability after directional focused energy blasting in coal seam was found increased. The maximum gas drainage volume was 10–40 times of the original one,with the effective radius of gas drainage reaching 7 meters. Besides,the directional focused energy blasting made little damage to the roof and floor of coal seam and the surround rock of roadway.