提高块煤率的爆破参数的数值优化

为了提高煤炭块率,炮孔间距的合理选取是提高块煤率的关键。通过有限元软件LS-DYNA2D,对封闭煤体中爆炸过程进行了数值模拟,研究表明,煤体中质点压应力、速度随着径向半径增大与时间的推移迅速减小。离爆心近处,质点的压应力与速度很大,但持续时间较短;离爆心远处,质点的压应力与速度较小,但持续时间较长。同时通过对提高块率爆破机理研究,得出了采用小药卷,控制眼距和爆破微差时间是提高爆破块率的主要途径。从而为提高煤块率的参数优化提供了一种切实可行的研究方法。

Numerical Optimization of Blasting Parameters for Increasing Lump Coal Rate

The rational selection of space between shot holes is the key to improvement of lump coal rate.The explosion of explosive in the sealed coal body is simulated using finite element software LS-DYNA2D.The research shows that the compressive stress and vibration velocity of particles in coal body reduce rapidly with radial radius and time increasing.The compressive stress and vibration velocity of particles are high near the blasting center,but their duration is shorter;The compressive stress and vibration velocity of particles are away from the blasting lower center,but their duration is more long.At the same time,through the mechanism study of blasting for increasing lump coal rate,the conclusion that adopting small explosive cartridges,controlling space between shot holes and time of delay in millisecond blasting are the main ways to increasing lump coal rate is drawn.It is a kind of feasible research means for optimization of blasting parameters for increasing lump coal rate.