Scientific and technical fundamentals for explosive destruction of the mass composed of rocks with different hardness

Purpose.To develop the technology for explosive destruction of solid inclusions in the mass of rocks with different hardness on the basis of established correlations between changes in the radius of hard streaks fragmenting, fracturing density and relative distance to the free surface during various initiating techniques in rocks of different hardness. Methods. Theoretical and experimental research into the development of scientific and technical fundamentals of explosive destruction of the mass of rocks with different hardness, which allows to determine the zone of hardening soft rocks located between solid inclusions. Findings. The developed technology for explosive destruction of mass of rocks with different hardness was implemented in the Tashkura quarry of Dzheroj-Sardara phosphate deposit of Navoiy MMC resulting in the economic effect of UZS 581.7 mln per 10.5 mln m3 of the extracted rock, while the economic effect in the free industrial and economic zone “Navoiy” was more than UZS 12 mln per 17000 m3 of the extracted rock. Originality. The conducted complex research resulted in the new technology for explosive destruction of the mass of rocks with different hardness, including hole boring, determination of the number and capacity of hard streaks in the process of boring, placing of the explosive charge in the hole, stemming. and blasting. Practical implications. Implementing the research results in the open quarry of Navoiy MMC allowed to make a significant contribution to the solution of the topical scientific and practical problem: efficient blast energy utilization during industrial explosions on hard streaks.