•  
  •  
 

Abstract

This article provides a detailed study of the physical and mechanical processes occurring during explosive crushing of rocks, with a special emphasis on the formation of cracks and changes in the granulometric composition of the massif. The main attention is paid to the influence of the blast loading parameters - the specific consumption of explosives (BC), charge diameter and line of least resistance (LLR) - on the average size and distribution of rock pieces. The distribution of the explosion energy for crushing, heat losses, seismic and impact effects, as well as the role of the energy transfer coefficient, depending on the physical and mechanical properties of the rock and the characteristics of the BC, are considered. The minimum and critical values of the specific consumption of BC, at which optimal crushing is achieved without excessive dust formation, are identified. Two characteristic zones of operation are described: at low specific consumptions, the crushing process is extremely sensitive to deviations in the design parameters, which complicates control, whereas at high specific consumptions, crushing becomes more stable and controllable. The analysis of the crushing uniformity index (n) shows that an increase in the LNS leads to an increase in the proportion of both large and small fractions, which can be useful for the processes of ball-free grinding and gravity concentration. The presented results contribute to the optimization of drilling and blasting operations, allowing to increase the efficiency of crushing, reduce costs and improve the quality of the final product.

First Page

41

Last Page

47

References

  1. Ivanov A.V. Rock Blasting: Theory and Practice. - Moscow: Nedra, 2018. - 320 p.
  2. Petrov S.N., Kuznetsov V.V. Physico-mechanical processes in the rock mass during blasting operations // Mining Journal. - 2017. - No. 5. - pp. 45-54.
  3. Smirnov D.V. Explosion energy and its distribution in the rock mass // Bulletin of the Mining University. - 2019. - Vol. 22, No. 3. - pp. 112-121.
  4. Kozlov I.M., Romanova E.A. Influence of charge parameters on the particle size distribution // Mining Technologies. - 2020. - No. 4. - pp. 66-75.
  5. Fedorov P.A. Optimization of drilling and blasting operations: methods and results // Mineral Resources of Russia. - 2021. - No. 2. - pp. 98-105.
  6. Vasiliev M.G., Nikolaev K.P. Specific explosive consumption and rock fragment size // Proceedings of the Russian Academy of Sciences. Mining Series. - 2018. - No. 7. - pp. 30-39.
  7. Chernov V.V. Rock blasting and fracture formation // Blasting Operations in Mining. - St. Petersburg: Gornaya Kniga, 2016. - pp. 56-68.
  8. Sidorov A.I. Rock Mechanics During Blasting: A Textbook. - Yekaterinburg: Ural Federal University, 2019. - 280 p.
  9. Lebedev V.S. Analysis of the parameters of the line of least resistance // Mining Mechanics. - 2017. - Vol. 13, No. 2. - pp. 70-79.
  10. Gusev Yu.P., Melnikov A.D. Influence of charge diameter on blasting efficiency // Mining Production Technology. - 2020. - No. 6. - pp. 44-52.
  11. Krylov E.V., Pashkov A.N. Empirical relationships in rock blasting // Mining Equipment and Technology. - 2018. - No. 3. - pp. 84-90.
  12. Markov V.I. Theory and practice of seismic effects in blasting // Geophysics Bulletin. - 2019. - Vol. 25, No. 1. - pp. 115-122.
  13. Nikiforov D.V. Uniformity index of fragmentation and particle size distribution // Mineral Processing. - 2021. - No. 1. - pp. 38-46.
  14. Zakharov V.N., Shestakov M.V. Mathematical modeling of blasting fragmentation processes // Applied Mechanics and Technology. - 2017. - No. 9. - pp. 28-35.
  15. Loginov A.A. Influence of charge parameters on rock particle size distribution // Mining Journal. - 2020. - No. 12. - pp. 24-33.
  16. Tarasov N.I., Zhukov V.A. Theory and Practice of Using Large-Caliber Charges in Quarries. - Yekaterinburg: UGGU, 2010. - 189 p.
  17. Petrenko V.P. Study of fragmentation parameters of rock mass with varying specific explosive consumption // Bulletin of the Mining Institute. - 2015. - Vol. 215. - pp. 87-95.

Download

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.