JOURNAL OF ROCK MECHANICS

JOURNAL OF ROCK MECHANICS

Investigating the effect of air deck length on fragmentation caused by blasting in Nardaghi limestone mine

Document Type : Original Article

Authors
1 School of Mining, College of Engineering, University of Tehran
2 School of Mining, College of Engineering. University of Tehran
Abstract
One of the most important technical and economic challenges in open-pit mining is the improvement and optimization of blasting patterns. Optimizing blasting parameters aims to achieve the right degree of rock fragmentation while reducing undesirable effects such as excessive vibration and fly rock. This topic has been extensively studied over the years. In the 1980s, it became clear that rock fragmentation from blasting significantly impacts secondary crushing, loading, and material handling. Consequently, the concept of optimal fragmentation became a key focus in mining engineering. In conventional blasting, less than 20% of the explosive energy is effectively used for breaking and moving the rock mass, while the majority of the energy causes unwanted phenomena. Research has shown that air deck blasting, which incorporates an air gap inside the blast hole, improves the efficient use of explosive energy by generating secondary energy. This method enhances fragmentation compared to traditional blasting and is considered a promising approach to optimize blasting performance and increase mining productivity.
Keywords
Subjects

[1]    Segarra Catasús, P. (2004). “Experimental analysis of fragmentarion, vibration and rock movement in open pit blasting” Doctoral dissertation, Minas.
[2]    Chiappetta, R. F., & Borg, D. G. (1983) . “Increasing productivity through field control and high-speed photography”. In Proc., 1st Int. Symp. on Rock Fragmentation by Blasting. Lulea, Sweden p.p 301-331.
[3]    Berta, G. (1990). Explosives and Engineering Tool, Italesplosivi, Milano. Chicago, United States.
[4]    Melnikov, N. V., & Marchenko, L. N. (1970). “Effective methods of application of explosion energy in mining and construction”. In ARMA US Rock Mechanics/Geomechanics Symposium (p.p. ARMA-70).
[5]    Mel’Nikov, N.V., Marchenko, L.N., Seinov, N.P., and Zharikov, I.F. (1979). A method of enhanced rock blasting by blasting, IPKON ANSSSR, Moscow, Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Isko-Paemykh. J Min Sci 6:32–42
[6]    Chiappetta, R. F. (2004). “New blasting technique to eliminate subgrade drilling, improve fragmentation, reduce explosive consumption and lower ground vibrations”. Journal of explosives engineering, 21(1), 10-12.
[7]    Saharan, M. R., Sazid, M., & Singh, T. N. (2017). “Explosive energy utilization enhancement with air-decking and stemming plug,‘SPARSH’”. Procedia engineering, 191, p.p 1211-1217. doi: 10.1016/j.proeng.2017.05.297.
[8]    Balakrishnan, V., & Pradhan, M. (2018). “Explosive consumption reduction by introducing hollow plastic tubes in explosive column”. ARPN Journal of Engineering and Applied Sciences. VOL. 13, NO. 14.
[9]     بخشنده امنیه، ح.؛ عارف مند، ا.؛ پورقاسمی، م.، (1398). "کنترل عقب زدگی و بهبود پارامترهای فنی و اقتصادی معدن". سنگ آهن میشدوان، نشریه مهندسی منابع معدنی. Doi:10.30479/jmre.2019.10436.1251
[10]  بخشنده امنیه، ح.؛ عارف مند، ا.؛ پورقاسمی، م.، (1399). " مطالعه خردشدگی حاصل از انفجار Power Deck  و مرسوم در معدن سنگ آهن میشدوان"، هفتمین کنفرانس مکانیک سنگ ایران.
[11] Cheng, R., Zhou, Z., Chen, W., & Hao, H. (2022). "Effects of axial air deck on blast-induced ground vibration". Rock Mechanics and Rock Engineering, p.p 1-17. https://doi.org/10.1007/s00603-021-02676-9.
[12] Gao, F., Tang, L., Yang, C., Yang, P., Xiong, X., & Wang, W. (2023). Blasting-induced rock damage control in a soft broken roadway excavation using an air deck at the blasthole bottom. Bulletin of Engineering Geology and the Environment, 82(3), 97. https://doi.org/10.1007/s10064-023-03087-6.
[13] Saqib, S., Usman Qureshi, M., Awais Rashid, H. M., Ali, D., & Rasool, A. M. (2024). A field-scale investigation into the strategic location of air decks for improved blasting performance. Archives of Mining Sciences, 391-407. DOI: https://doi.org/10.24425/ams.2024.151442.
[14] Moradi, M., Ebrahimi Farsangi, M. A., Mansori, H., & Saffari Pour, M. (2024). An investigation into the performance of bottom air-deck method in the presence of water, using SPH-FEM. Journal of Analytical and Numerical Methods in Mining Engineering, 14(41), 43-54. DOI: 10.22034/ANM.2025.21431.1631.
[15]  عارف مند, ابراهیم , بخشنده امنیه, حسن , مجدی, عباس و وحیدی, مهدی . (1403). تحلیل عددی تاریخچه فشار چال و تخریب توده‌سنگ ناشی از انفجار به روش‌های مرسوم و بالشتک هوایی. نشریه مهندسی منابع معدنی, 9(4), 81-93. doi: 10.30479/jmre.2024.19413.1668
[16]  Chung, S. H., & Katsabanis, P. D. (2000). Fragmentation prediction using improved engineering formulae. Fragblast, 4(3-4), 198-207.‏