AAB Project LLC, Yerevan, Republic of Armenia

G. A. Agaronyan, Head of Drilling and Blasting, Candidate of Engineering Sciences

National Polytechnic University of Armenia, Yerevan, Republic of Armenia

I. S. Avanesova, Candidate of Engineering Sciences, Associate Professor, inna.avanesova.1969@mail.ru

Efficient mining of complex orebodies means maximal extraction of ore at minimum loss and dilution. Complex orebodies occur in nonuniform rock masses composed of rocks of different acoustic stiffness and strength. Blasting of such orebodies induces mixing of ore and barren rocks at their interfaces, and ore gets diluted with barren rocks. Reducing ore and barren rock mixing is only possible through a decrease in the width of the blast muck pile with regard to ore and rock distribution in it. It is proved that efficiency of complex orebody mining depends on obtaining of ore and nonmetallic rock muck piles. It is found that in blasting at complex faces, it is very important to increase the duration of the stress wave and reduce the peak pressure of the gaseous products of explosion, thereby increasing the destructive effect of the blast. A new technology of blasting is proposed using borehole charges composed of a mixture of industrial explosives and expanded polystyrene granules. The technology ensures decrease in the limiting pressure of gaseous blast products, increase in the duration of the blast impact on
the treated medium, and creation of a cut-off gap (artificial air barrier) along the contour of standard-grade and substandard ores. This helps reduce the degree of their mixing and obtain standard-grade and substandard ore muck piles of different shapes and sizes.

1. Rakishev B. R. Models of rock slumping on ledges at different blasting techniques. Journal of Mining Institute. 2007. Vol. 171. pp. 39–44.
2. Paramonov G. P., Lisevich V. V. Forecasting of parameters of a rock mass collapse when blasting work. Mezhdunarodnyy nauchno-issledovatelskiy zhurnal. 2016. No. 4-6(46). pp. 100–103.
3. Khokhlov S. V., Vinogradov Yu. I., Noskov A. P., Bazhenova A. V. Predicting displacements of ore body boundaries in generation of blasted rock pile. MIAB. 2023. No. 3. pp. 40–56.
4. Anistratov Yu. I., Anistratov K. Yu. Opencast Mining Technology : Textbook. 3^rd revised and enlarged edition. Moscow : Gornoe delo, 2007. 476 p.
5. Rakishev B. R. Stripping of Open-Pit Fields and Open Pit Mining Systems. Almaty, 2013. 304 p.
6. Laptev Yu. V., Kantemirov V. D., Yakovlev A. M. Computer modeling of rock mass breakup in selective mining. Almanakh sovremennoy nauki i obrazovaniya. 2014. No. 5-6(84). pp. 92–96.
7. Rakishev B. R., Shampikova A. Kh., Kazangapov A. E. Mining-geological characteristics of rocked complex structural blocks. Vzryvnoe delo. 2018. No. 120/77. pp. 82–93.
8. Rakhmanov R. A., Loeb J., Kosukhin N. I. Estimation of ore contour movements after the blast using the BMM system. Journal of Mining Institute. 2020. Vol. 245. pp. 547–553.
9. Baranowski P., Kucewicz M., Pytlik M., Małachowski J. Study of rock fracture under blast loading. Bulletin of the Polish Academy of Sciences Technical Sciences. 2022. Vol. 70, No. 5. ID e141723.
10. Agaronyan G. A., Avanesova I. S., Ovsepyan V. G. A new technology for conducting largescale explosions at quarries. Vestnik Natsionalnogo politekhnicheskogo universiteta Armenii. Metallurgiya, materialovedenie, nedropolzovanie. 2023. No. 1. pp. 78–88.
11. Kryukov G. M., Dokutovich M. I., Zharovonko S. N. The reduction range and the output of the oversized lumps during the explosive scarifying of rocks at open pits. MIAB. 2011. No. 5. pp. 347–351.
12. Choudhary B. S. Firing patterns and its effect on muckpile shape parameters and fragmentation in quarry blasts. International Journal of Research in Engineering and Technology. 2013. Vol. 2, Iss. 9. pp. 32–45.
13. Agaronyan G. A. A new technology for regulating actions of energy of mass explosion at the open pits. Izvestiya Natsionalnoy akademii nauk RA i Gosudarstvennogo inzhenernogo universiteta Armenii. Seriya tekhnicheskikh nauk. 2021. Vol. 74, No. 3. pp. 278–289.
14. Agyei G., Owusu-Tweneboah M. A comparative analysis of rock fragmentation using blast prediction results. Ghana Mining Journal. 2019. Vol. 19, No. 1. pp. 49–58.
15. Agaronyan G. A., Agaronyan A. G. Modeling the process of the displacement and formation of the exploded rock mass disintegration at an explosion in a fractured medium. Vestnik Natsionalnogo politekhnicheskogo universiteta Armenii. Metallurgiya, materialovedenie, nedropolzovanie. 2018. No. 1. pp. 84–95.
16. Roy M. P., Mishra A. K., Agrawal H., Singh P. K. Blast vibration dependence on total explosives weight in open-pit blasting. Arabian Journal of Geosciences. 2020. Vol. 13. DOI: 10.1007/s12517-020-05560-y
17. Jia B., Ling T., Hou S., Liu D. Application of variational mode decomposition based delay time identification in short millisecond blasting. Transaction of Beijing Institute of Technology. 2021. Vol. 41, No. 4. pp. 341–348.
18. Kazakov N. N., Viktorov S. D., Shlyapin A. V., Lapikov I. N. Fragmentation of Rocks by Blasting in Quarrying. Moscow : RAN, 2020. 520 p.