装药结构对深孔爆破粉矿产出率的影响研究

针对南方某矿大直径深孔爆破生产过程中因粉矿产出量过高而导致的矿石损失问题，开展了不同装药结构对粉矿率的影响研究。基于ANSYS/LS-DYNA软件建立了6种装药结构模型，从模型单元失效比例和爆后块度分布两个方面进行了分析比较。结果表明，在炮孔、炸药直径不变的情况下，通过改变单层药包条数和空气间隔距离的方式，得到装药结构2(1条炸药-1.0 m间隔-1条炸药)的粉矿比例为11.53%、大块比例为5.43%，且其单个区域失效比例方差和单个区域与整体区域失效比例差值方差均较小，为最优炮孔装药结构。工程实践结果表明，装药结构2可以有效降低矿石粉矿率和大块率，提高矿石资源回收率，提高矿山经济效益。

Influence of Charge Structure on the Output Rate of Fragmentation in Deep-Hole Blasting

Aiming at the problem of ore losses caused by high output rate of fragmentation in the production process by using large-diameter deep-hole blasting in a mine in South China, the influence of different charge structure on the percentage of fragmentation was studied. Based on ANSYS/LS-DYNA software, six kinds of charge structure models were established, which were analyzed based on comparison in terms of the failure ratio of model units and fragment size distribution after explosion. The results showed that the charge structure 2 (two bars of explosive with 1.0 m interval) can be chosen as the optimal explosive charge structure. It is shown that with the same diameter for blasthole and explosive, such charge structure can bring in a percentage of fragmentation of 11.53% and a percentage of large-size fragment of 5.43% by changing the bar number of single-layer charge and the air gap. Also both the variance of its single unit failure ratio and the variance of difference between single unit failure ratio and the whole area failure ratio were smaller. The engineering practice results showed that the charge structure 2 could effectively reduce the percentage of fragmentation and large-size fragment, thus improving the recovery rate of ore resources and bringing economic benefits to mines.