孔内爆炸冲击波衰减规律研究

Study on the Propagation Law of Explosion Shock Wave in Hole

摘要: 炮孔会对炸药产生的爆炸冲击波产生较大的影响，这种影响主要表现在岩石约束对爆炸冲击波的传播方式、衰减速度、孔壁反射等方面。采用理论计算分析炸药爆炸时爆炸冲击波在开放环境和炮孔中传播方式的差异性，运用ANSYS/LS-DYNA数值模拟两种工况，验证理论计算和软件数据，通过分析表明孔壁的约束作用，削弱了爆炸冲击波在空气中的衰减速度，通过拟合爆炸冲击波衰减曲线，得出开放环境与炮孔中冲击波衰减系数比为1.65；炮孔底部最大反射波叠加压力是入射波的21.5倍，会极大增强炮孔底部压力。

Abstract: The blasthole will have a great influence on the explosion shock wave produced by explosives, which is mainly manifested in the propagation mode, attenuation velocity and hole wall reflection of the explosion shock wave caused by rock restraint. The difference of the propagation mode of explosion shock wave in open environment and blast hole during explosive explosion is analyzed by theoretical calculation. ANSYS/LS-DYNA numerical simulation is used to verify the theoretical calculation and software data. The analysis shows that the restraint effect of hole wall weakens the attenuation velocity of explosion shock wave in air. By fitting the explosion shock wave attenuation curve, it is concluded that the shock wave attenuation coefficient ratio between the open environment and the blasthole is 1.65; the maximum reflected wave superimposed pressure at the bottom of the blasthole is 21.5 times that of the incident wave, which will greatly increase the pressure at the bottom of the blasthole.