Технологические способы ведения взрывных работ, позволяющие безопасно управлять действием взрыва в массиве горных пород

Abstract

Purpose. The work is devoted to improving the efficiency and safety of the escarpous blasting of rocks by borehole charges of explosives of a new design at iron ore quarries. In the thesis, the features of the process of explosive destruction of rocks by well charges of various designs are investigated. The dependences of their dynamics of explosive destruction on the physicomechanical properties of rocks are established, and the relationship between the distribution of energy of destruction in the medium and the magnitude of the specific impulse of the explosion is determined. Metodology. The obtained regularities of the impulse effect of an explosion associated with the overall energy balance imparted to a destructible medium can serve as a scale for evaluating the effectiveness of the action of well charges exploded simultaneously or through the definition of deceleration. Based on the obtained theoretical and laboratory results, a new design of a downhole charge of explosives with an air cavity in the bottom of the well has been developed. Findings. A feature of this design of the borehole charge is the concentration of the explosion energy in the bottom of the well. The optimal parameters of the air cavity and the location of the initiator relative to it in the technology of blasting have been established. Originality of the work lies in the fact that the conducted industrial tests of a new design of a borehole charge with an air cavity in the bottom part of the well showed its high efficiency. Practical value lies in achieving a reduced specific consumption of explosives. This technological process ensures uniform crushing of the blasted rock mass over the entire height of the ledge and high-quality development of the bottom of the ledge, which opens up real opportunities for the elimination of the re-drilling of the well at the inferior explosive blasting of rocks.