台阶爆破间隔装药最佳间隔位置确定方法

Determination Method for Optimum Spacing Position of Spaced Loading of Bench Blasting

为了从理论上分析不同间隔位置对爆破效果的影响,选出理论上最优的间隔位置,运用大型动力分析软件LS-DYNA对孔底间隔、孔口间隔和中部间隔进行数值模拟,首先,从峰值振速衰减规律进行分析,得出中部间隔峰值振速比孔底间隔和孔口间隔峰值振速均小;其次,从最大主应力角度进行分析,选取炮孔顶部单元,得出3种工况下最大主应力均大于岩石的动态抗拉强度;最后,从峰值振速结合最大主应力进行分析,得出中部间隔降振效果最好且对爆破效果无影响,为理论上最佳方案。

In order to analyze the effect of different interval position on the blasting effect in theory,the optimal interval location is selected.Using the large-scale dynamic analysis software LS-DYNA,the numerical simulation for hole bottom interval,orifice interval and middle interval is conducted.First,from analyzing the attenuation laws of peak vibration velocity,the peak vibration velocity of middle interval is smaller than hole bottom interval and orifice interval; second,selecting the top unit of the hole,from the angle of maximum principal stress,the maximum principal stress of the three cases are all more than the dynamic tensile strength of rock.In the end,based on the analysis of the maximum principal stress and the peak vibration velocity,it is concluded that the middle interval charging is the best scheme and has no effect on the blasting effect.