3种现场混装炸药耦合装药炮孔壁峰值压力计算

Calculation of peak pressure on the wall of a coupled charge blasting hole for 3 explosive mixtures

炮孔壁峰值压力是产生炮孔周围应力场的源头,是造成孔壁附近岩石破坏的强动载荷。对于耦合装药,炮孔壁峰值压力是由爆轰波碰撞孔壁而生产的,通常这种碰撞是斜碰撞,并不是正碰撞。基于这样的物理事实,通过对现有耦合装药孔壁压力计算方法行了评述,并提出斜碰撞的炮孔壁峰值压力计算方法。结果表明,爆轰冲击理论计算结果接近实测值和数值模拟值;引入斜入射系数可计算爆轰波斜入射时孔壁压力,爆轰波碰撞在炸药与孔壁的分界面上,在不同的入射角度下,作用在孔壁的压力是不同的。孔壁压力与炸药特性、岩体特性、爆轰波曲率半径、爆轰波入射角等有关。

The peak pressure on the wall of the blasting hole is the source of the stress field surrounding the hole and it is a powerful dynamic load that destroys the rock near the hole wall.The detonation wave collides with the borehole wall to generate the peak pressure at the condition of coupled charge blasting hole,which typically occurs at an oblique angle rather than a regular one.Drawing from these physical insights,this work analyzes the existing methods for calculating hole wall pressure in the context of coupled charge and proposes the peak pressure calculation method for the blasting hole wall considering oblique collision.The findings demonstrate that the theoretical calculation formula of the detonation impact yields results that are more in line with observed values and numerical simulations.When the detonation wave is obliquely incident on the hole wall,the pressure acted on the hole wall could be determined by the introduction of obliquely incidence coefficient.The explosion pressure on the hole wall varies with the different angles of incidence and is influenced by the characteristics of the explosives,properties of the rock,the radius of curvature of the detonation wave,and the angle of incidence of the detonation wave.