炸药爆轰性能变化对破岩效果影响的实验研究

在耦合装药条件下 ,通过两组对比爆破破碎实验 ,研究了炸药爆轰性能变化对破岩效果的影响。第一组实验 ,采用相同的冲击能 (Es)与膨胀能 (Eb)比值的柱状药包 ,爆破破碎不同波阻抗的混凝土介质 ;第二组实验 ,采用不同的冲击能 (Es)与膨胀能 (Eb)比值的柱状药包 ,分别爆破破碎相同的混凝土介质。实验结果表明 ,随着炮孔孔壁上产生的透射应力波峰值 (Pt)的增大 ,第一组实验的小尺寸破碎块度的产出量 (MSF)随之上升 ,而第二组实验的MSF随之下降。分析结果表明 ,药包爆轰性能的改变 ,使得Es 和Eb的加载水平发生相应的变化 ,进而影响到MSF的变化趋势。MSF取决于Es 和Eb 加载的共同作用结果。这表明除Es 冲击加载外 ,Eb 动态加载在爆破破岩过程中起了积极作用。

Experimental investigation on the effect of change in explosive detonation in rock fragmentation

In order to investigate into the effect of change in explosive detonation on rock fragmentation under the explosion of a coupling charge within borehole, two groups of contrast fragmentation experiments were conducted in cylindrical concrete models. In the first group, the charge with the same ratio of shock energy (E s) and bulge energy E b was used to break the models with different acoustic impedance. In the second group, the models with the constant impedance were separately broken by the charges with the different ratio of E s and E b. The experimental results showed that, with increasing in the peak (P t) of the transmission compressive stress in the borehole's wall, the mass of small size fragments (MSF) of the first group rose while that of the second group decreased. The analysis results indicated that change in the explosive detonation of a charge results in change in the level of both Es impact and E b loading dynamically against the surrounding media. The tendency in MSF depends on both E s impact and E b loading dynamically was affected. Besides the effect of E s impact, MSF is strongly correlated with E b dynamically loading the media.