Optimum Sublevel Height and Drift Spacing in Sublevel Cave Mining Based on Random Medium Theory
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Weak rock mass and poor flow of material can cause excessive ore loss and dilution in sublevel caving. This paper proposes a method to establish design parameters for an inclined deposit within a weak rock mass and evaluates its effectiveness through a case study. In order to solve the problem of low production capacity and poor safety conditions of sublevel caving mining at the Yingfangzi silver mine in China and to ensure a smooth production from the refractory ore body, it is necessary to select appropriate stope structure parameters. Based on random medium theory of gravity flow and the improved equation of ore discharge in random medium, an end wall drawing experiment is carried out to determine the optimum design and flow parameters. It was observed from the experiment that, due to the influence of the randomness of particle movement, there is a mismatch in the flow parameter measurement. The flow characteristics and distribution of the marker particles are different from that of the tested particles resulting in large drawbody shape distortion. The study finds that the flow parameters obtained by the new method are more practical and account for drawpoint width and recommends that the new method for determining the sublevel stope height is used when the drawbody is a non-standard ellipsoid. The outcomes have shown a significant reduction in the dilution and improvement in the recovery rates, and the safety and efficiency of mining have been greatly improved.
KeywordsRandom medium theory Sublevel caving Sublevel height Drift spacing Stope structure parameters
This work was supported by the National Natural Science Foundation of China [grant number 51534003], the Ministry of Science and Technology of the People’s Republic of China [grant number 2016YFC0801601] and the China Scholarship Council [grant number 201706080072].
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The Conflict of Interest Statement
On behalf of all authors, the corresponding author states that there is no conflict of interest.
- 2.Durrheim RJ (2010) Mitigating the risk of rockbursts in the deep hard rock mines of South Africa: 100 years of research. Society for Mining, Metallurgy, and Exploration, Inc., ISBN 978-0-87335-322-9, pp 156-171Google Scholar
- 3.Bull G, Page CH (2000) Sublevel caving–today’s dependable low-cost ‘ore factory’. MassMin 2000 Proceedings. Brisbane: The Australasian Institute of Mining and Metalurgy, pp 537–556Google Scholar
- 6.Hustrulid W, Kvapil R (2008) Sublevel caving–past and future. Proceedings of the 5th international conference and exhibition on mass mining, Luleå University Press, Luleå, pp 107–132Google Scholar
- 7.Woodruff SD (1966) Methods of working coal and metal mines: planning and operations, M. ElsevierGoogle Scholar
- 12.Brady B, Brown E (2007) Longwall and caving mining methods. Rock mechanics for underground mining, pp 430–483. https://doi.org/10.1007/978-1-4020-2116-9_15
- 13.KumarHaldar S (2018) Chapter 12 - Elements of Mining. Mineral Exploration (Second Edition) Principles and Applications, pp 229–258. https://doi.org/10.1016/B978-0-12-814022-2.00012-5 CrossRefGoogle Scholar
- 19.Ren FY (1994) The stochastic medium method of ore-drawing and its application. Metallurgical Industry Press, Beijing (in Chinese)Google Scholar
- 21.Ren FY (1992) Theory and practical application of random medium for ore drawing. Northeast University, Shenyang (in Chinese)Google Scholar
- 22.Tao GQ, Ren FY, Liu ZD et al (2010) Research on improvement of the stochastic medium theory for ore drawing. J Min Saf Eng 27(02):239–243 (in Chinese)Google Scholar
- 23.Wimmer M (2010) Gravity flow of broken rock in sublevel caving (SLC) – state-of-the-art. Luleå University of Technology, LuleåGoogle Scholar
- 25.Brady BHG, Brown ET (2004) Rock mechanics for underground mining, 3rd edn. Kluwer, DordrechtGoogle Scholar
- 26.Power GR (2004) Modelling granular flow in caving mines: large scale physical modelling and full scale experiments, PhD thesis, University of QueenslandGoogle Scholar