Optimum Sublevel Height and Drift Spacing in Sublevel Cave Mining Based on Random Medium Theory

  • Kunpeng YuEmail author
  • Fengyu Ren
  • Gideon Chitombo
  • Ruslan Puscasu
  • Liangliang Kang


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.


Random 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].

Compliance with Ethical Standards

The Conflict of Interest Statement

On behalf of all authors, the corresponding author states that there is no conflict of interest.


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Copyright information

© Society for Mining, Metallurgy & Exploration Inc. 2020

Authors and Affiliations

  1. 1.School of Resources and Civil EngineeringNortheastern UniversityShenyangChina
  2. 2.Sustainable Minerals InstituteThe University of QueenslandSt LuciaAustralia
  3. 3.Mining3Pinjarra HillsAustralia
  4. 4.CSIRO Mineral ResourcesQueensland Centre for Advanced TechnologiesPullenvaleAustralia
  5. 5.Patent Examination Cooperation Hubei Center of the Patent OfficeWuhanChina

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