On the merits of modified sublevel caving mining method – a case study

• Autorzy: Adams Kenneth K. , Chen Tuo , Sainoki Atsushi , Mitri Hani S.

Identyfikatory

DOI

10.24425/ams.2023.148149

• Języki publikacji: EN

Abstrakty

EN

Sublevel caving (SLC) mining method has several features that make it one of the preferred methods for ore extraction due to its high productivity and early access to ore recovery. However, there are some major challenges associated with the SLC method such as ground surface subsidence, high unplanned ore dilution, and the potential for air blast. To remedy these shortcomings, a recent approach has been to modify the SLC method by introducing rockfill into the void atop the production zone to provide continued support for the host rock and prevent it from caving. This paper discusses in detail the merits of the Modified SLC or MSLC. In comparison with other long-hole stoping methods that are predominantly practiced in metal mines, the MSLC method boasts several advantages. Early production achieved from the topmost level helps reduce the payback period. Productivity is enhanced due to multilevel mining without the use of sill pillars. The cost of backfilling is significantly reduced as there is no need for the construction of costly backfill plants. Continuous stoping is achieved without delays as mining and backfilling take place concurrently from separate mining horizons. A significant reduction in underground development costs is achieved as fewer slot raises and crosscuts are required for stope preparation. These merits of the Modified SLC method in steeply dipping orebodies are discussed by way of reference to real-life mine case studies. Dilution issues are addressed, and the benefits of top-down mining are explained. Typical mine design, ventilation, materials handling, and mining schedules are presented. Geomechanics issues associated with different in-situ stress environments are discussed and illustrated with simplified mine-wide 3D numerical modeling study.

Słowa kluczowe

EN

underground mining; long hole mining; sublevel caving; modified sublevel caving; surface subsidence; ore dilution; backfill; mine design; numerical modelling

PL

górnictwo podziemne; osiadanie górnicze; modelowanie numeryczne; kopalnia

• Wydawca: Instytut Mechaniki Górotworu PAN
• Czasopismo: Archives of Mining Sciences
• Rocznik: 2023
• Tom: Vol. 68, no. 4
• Strony: 543--569
• Opis fizyczny: Bibliogr. 34 poz., rys., tab., wykr.

Twórcy

autor

Adams Kenneth K.

• McGill University, Canada

• https://orcid.org/0009-0002-6310-4520

autor

Chen Tuo

• McGill University, Canada

• https://orcid.org/0000-0002-6551-4091

autor

Sainoki Atsushi

• Kumamoto University, Japan

• https://orcid.org/0000-0003-2754-4801

autor

Mitri Hani S.

• McGill University, Canada

• https://orcid.org/0000-0002-6482-7424+

Bibliografia

• [1] S. Xu, F.T. Suorineni, L. An, Y. Li, A study of gravity flow principles of sublevel caving method in dipping narrow veins. Granular Matter 19 (4), 1-13 (2017). DOI: https://doi.org/10.1007/s10035-017-0748-z.
• [2] Q. Jia, G. Tao, Y. Liu, S. Wang, Laboratory study on three-dimensional characteristics of gravity flow during longitudinal sublevel caving. International Journal of Rock Mechanics and Mining Sciences 144, 104815 (2021). DOI: https://doi.org/10.1016/j.ijrmms.2021.104815.
• [3] I. Janelid, R. Kvapil, Sublevel caving. In International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts 3 (2), 129-132 Pergamon (1966). DOI: https://doi.org/10.1016/0148-9062(66)90004-0.
• [4] G. Tao, M. Lu, X. Zhang, R. Zhang, Z. Zhu, A new diversion drawing technique for controlling ore loss and dilution during longitudinal sublevel caving. International Journal of Rock Mechanics and Mining Sciences 113, 163-171 (2019). DOI: https://doi.org/10.1016/j.ijrmms.2018.12.006.
• [5] M. Svartsjaern, A prognosis methodology for underground infrastructure damage in sublevel cave mining. Rock Mechanics and Rock Engineering 52 (1), 247-263 (2019). DOI: https://doi.org/10.1007/s00603-018-1464-7.
• [6] E. Can, Ş Kuşcu, M.E. Kartal, Effects of mining subsidence on masonry buildingsin Zonguldak hard coal region in Turkey. Environmental Earth Sciences 66 (8), 2503-2518 (2012). DOI: https://doi.org/10.1007/s12665-011-1473-2.
• [7] L. Nie, H. Wang, Y. Xu, Z. Li, A new prediction model for mining subsidence deformation: the arc tangent function model. Natural Hazards 75 (3), 2185-2198 (2015). DOI: https://doi.org/10.1007/s11069-014-1421-z.
• [8] F. Ma, H. Zhao, R. Yuan, J. Guo, Ground movement resulting from underground backfill mining in a nickel mine (Gansu Province, China). Natural Hazards 77 (3), 1475-1490 (2015). DOI: https://doi.org/10.1007/s11069-014-1513-9.
• [9] X. Zhao, Q. Zhu, Analysis of the surface subsidence induced by sublevel caving based on GPS monitoring and numerical simulation. Natural Hazards 103 (3), 3063-3083 (2020). DOI: https://doi.org/10.1007/s11069-020-04119-0.
• [10] A. van As, Subsidence definitions for block caving mines (2003).
• [11] K.S. Woo, E. Eberhardt, D. Elmo, D. Stead, Empirical investigation and characterization of surface subsidence related to block cave mining. International Journal of Rock Mechanics and Mining Sciences 61, 31-42 (2013). DOI: https://doi.org/10.1016/j.ijrmms.2013.01.015.
• [12] H. Parmar, A. Yarahmadi Bafghi, M. Najafi, Impact of ground surface subsidence due to underground mining on surface infrastructure: the case of the Anomaly No. 12 Sechahun, Iran. Environmental Earth Sciences 78, 1-14 (2019). DOI: https://doi.org/10.1007/s12665-019-8424-8.
• [13] S. Jianjun, H. Chunjian, L. Ping, Z. Junwei, L. Deyuan, J. Minde, Z. Jingkai, S. Jianying, Quantitative prediction of mining subsidence and its impact on the environment. International Journal of Mining Science and Technology 22 (1), 69-73 (2012). DOI: https://doi.org/10.1016/j.ijmst.2011.07.008.
• [14] R.S. Suglo, S. Opoku, An assessment of dilution in sublevel caving at Kazansi Mine. International Journal of Mining and Mineral Engineering 4 (1), 1–16 (2012). DOI: https://doi.org/10.1504/IJMME.2012.047996.
• [15] R.C. Pakalnis, R. Poulin, J. Hadjigeorgiou, Quantifying the cost of dilution in underground mines. In International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts 5 (33), 233A (1996).
• [16] T. Chen, H.S. Mitri, Strategic sill pillar design for reduced hanging wall overbreak in longhole mining. International Journal of Mining Science and Technology, 31 (5), 975-982 (2021). DOI: https://doi.org/10.1016/j.ijmst.2021.09.002.
• [17] A.L. Shao, A soffit type of sublevel caving method with a steel-concrete artificial roof. Chinese patent. 201110232079.7; 2011-8-15 [in Chinese].
• [18] T.M. Malakhov, Drawing of Caving Ore Block. Beijing: Metallurgical Industry Press (1958).
• [19] J. Oh, M. Bahaaddini, M. Sharifzadeh, Z. Chen, Evaluation of air blast parameters in block cave mining using particle flow code. International Journal of Mining, Reclamation, and Environment 33 (2), 87-101 (2019). DOI: https://doi.org/10.1080/17480930.2017.1342064.
• [20] G.E. Flores, PhD thesis, Rock mass response to the transition from open pit to underground cave mining, Julius Kruttschnitt Mineral Research Centre, The University of Queensland, Australia (2005).
• [21] T.R. Stacey, J.A.C. Diering, N. Rigby, Stability predictions based on back analysis of collapsed crown pillar, Epoch mine, Zimbabwe. In African Mining’91. Institution of Mining and Metallurgy, 55-60 (1991). DOI: https://doi.org/10.1007/978-94-011-3656-3_6.
• [22] R. De Nicola, M. Fishwick, An underground air blast–Codelco-Chile–Division Salvador. Proceedings of MassMin 2000, 173-178 (2000).
• [23] R. Gómez, M. Loyola, S. Palma, C. Valdés, Experimental study of the inrush of fines events in caving mining. International Journal of Rock Mechanics and Mining Sciences 169, 105436 (2023). DOI: https://doi.org/10.1016/j.ijrmms.2023.105436.
• [24] G. Flores, Major hazards associated with cave mining: are they manageable? In Proceedings of the First International Conference on Mining Geomechanical Risk, Australian Centre for Geomechanics, Perth, 31-46 (2019). DOI: https://doi.org/10.36487/ACG_rep/1905_0.3_Flores-Gonzalez.
• [25] E. Samosir, J. Basuni, E. Widijanto, T. Syaifullah, The management of wet much at PT Freeport Indonesia’s Deep Ore Zone mine, in H Schunnesson & E Nordlund (eds), Proceedings the 5th International Conference and Exhibition on Mass Mining, Lulea University of Technology, Lulea, 323-332 (2008).
• [26] T. Chen, H.S. Mitri, Strategies for surface crown pillar design using numerical modelling – A case study. International Journal of Rock Mechanics and Mining Sciences 138, 104599 (2021). DOI: https://doi.org/10.1016/j.ijrmms.2020.104599.
• [27] Z.T. Beniawski, Rock mass classifications in rock engineering. Exploration for Rock Engineering 1, 97-106 (1976). DOI: https://doi.org/10.3124/segj.58.112.
• [28] H.S. Mitri, R. Edrissi, J. Henning, Finite element modeling of cable-bolted stopes in hard rock ground mines. In: SME Annual Meeting, Albuquerque, New Mexico, 94-116 (1994).
• [29] A. Letamo, B. Kavitha, T.P. Tezeswi, Seismicity pattern of African regions from 1964–2022: b-value and energy mapping approach. Geomatics, Natural Hazards and Risk 14 (1), (2023). DOI: https://doi.org/10.1080/19475705.2023.2197104.
• [30] I. Vennes, H. Mitri, D. R. Chinnasane, M. Yao, Large-scale destress blasting for seismicity control in hard rock mines: a case study. International Journal of Mining Science and Technology 30 (2), 141-149 (2020). DOI: https://doi.org/10.1016/ijmst.2020.01.05.
• [31] L.A.M. Castro, R.P. Bewick, T.G. Carter, An overview of numerical modeling applied to deep mining. Innovative Numerical Modeling in Geomechanics, 393-414 (2012). DOI: https://doi.org/10.1201/b12130-22.
• [32] A. Sainoki, H. S. Mitri, M. Yao, D. Chinnasane, Discontinuum modeling approach for stress analysis at a seismic source: Case Study. Rock Mechanics and Rock Engineering 49, 4749-4765 (2016). DOI: https://doi.org/10.1007/s00603-016-1089-7.
• [33] G. Herget, Stress assumptions for underground excavations in the Canadian Shield. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts 24 (1), 95-97 (1987). DOI: https://doi.org/10.1016/0148-9062(87)91238-1.
• [34] M.S. Diederichs, P.K. Kaiser, E. Eberhardt, Damage initiation and propagation in hard rock during tunneling and the influence of near-face stress rotation. International Journal of Rock Mechanics and Mining Sciences 41, 785-812 (2004). DOI: https://doi.org/10.1016/j.ijrmms.2004.02.003.

Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2024)