Исследования детонационных характеристик эмульсионных взрывчатых веществ, применяемых на железорудных карьерах

Abstract

The paper outlines the main trends in the development of blasting operations used in iron ore mining. It is pointed out that due to the tendency to raise the weight of blast charges, an increasing negative effect of the seismic blast action is observed on the surrounding rock masses and protected facilities. In order to identify efficient ways to reduce seismic impact on the final pit outline and the protected facilities, a set of field tests was performed on the detonation characteristics of emulsion explosives for the conditions of iron ore open pits. The paper demonstrates that petering-out of detonation is observed for the extended charge of explosives. Analysis of causes for the detonation failure showed that it can be related to non-observance of the technology to charge watered boreholes, failures to meet the technological process when manufacturing the emulsion explosivuseful minerals, explosives, protected facilities, seismic action, detonation, emulsion explosives, charge, deflagration, booster, primer, environmentes, blast hole collapses caused by premature firing of the neighboring holes that have bigger delays. Analysis of the research results into the detonation characteristics of emulsion explosives showed that the probability of shifting from detonation to a low-velocity mode or deflagration is related to the length of the emulsion charge, the distance from the booster and probability is increasing at the lower (reverse) method of firing the charge. It is concluded that in order to increase the reliability of detonation of the emulsion explosives it is required to minimize the length of the emulsion part of the charge and to use combined firing methods of the blast charges.