Vance Press
Register Login

Rock Mechanics Letters

Open Access Research Article

Prediction of the height of caving zone above the undercut in block caving mining method

by Behnam Alipenhani 1,* Abbas Majdi 1 Hassan Bakhshandeh Amnieh 1  and  Erfan Amini 1
1
School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran
*
Author to whom correspondence should be addressed.
Received: 27 September 2024 / Accepted: 12 October 2024 / Published Online: 12 October 2024

Abstract

The block caving is one of the most commonly used methods in underground mining of massive, low/high grades, and deep deposits. As a result of undercutting, caving occurs and propagates toward the upper part of the ore block. It is essential to predict the height of caved ore and its volume based on shape of the caved zone to make an economic decision. This paper describes the mechanism of height of the caving zone development. Consequently, four new mathematical models (prismatic, parabolic, cubic, and hemispheric) are proposed to estimate the height of this caving zone. The results are compared with the existing approaches. The proposed methods have proven that the height of caving zone has a linear relationship with the uniaxial tensile and compressive strengths and the height of undercut as well. Also, the height of the caving zone has a negative exponential relationship with unit weight of undercut roof materials and its expansion factor. The Height of the caving zone of the prismatic model is 1.5 times higher than the parabolic model and 1.3 times higher than the hemispheric model. The cubic model estimates the lowest height of the caving zone (0.3 times the height estimated by the prismatic model). The average height of the caving zone, taking the average unit weight of 27 KN/m3 into account, is about 69.4 times the tensile strength, 5.8 times the uniaxial compressive strength of the rock mass, and 18.8 times the height of the undercut.


Copyright: © 2024 by Alipenhani, Majdi, Bakhshandeh Amnieh and Amini. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) (Creative Commons Attribution 4.0 International License). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Show Figures

Share and Cite

ACS Style
Alipenhani, B.; Majdi, A.; Bakhshandeh Amnieh, H.; Amini, E. Prediction of the height of caving zone above the undercut in block caving mining method. Rock Mechanics Letters, 2024, 1, 5. https://doi.org/10.70425/rml.202401.5
AMA Style
Alipenhani B, Majdi A, Bakhshandeh Amnieh H, Amini E. Prediction of the height of caving zone above the undercut in block caving mining method. Rock Mechanics Letters; 2024, 1(1):5. https://doi.org/10.70425/rml.202401.5
Chicago/Turabian Style
Alipenhani, Behnam; Majdi, Abbas; Bakhshandeh Amnieh, Hassan; Amini, Erfan 2024. "Prediction of the height of caving zone above the undercut in block caving mining method" Rock Mechanics Letters 1, no.1:5. https://doi.org/10.70425/rml.202401.5
APA Style
Alipenhani, B., Majdi, A., Bakhshandeh Amnieh, H., & Amini, E. (2024). Prediction of the height of caving zone above the undercut in block caving mining method. Rock Mechanics Letters, 1(1), 5. https://doi.org/10.70425/rml.202401.5

Article Metrics

Article Access Statistics

References

  1. Brown ET. Block caving geomechanics. JKMRC Monograph Series in Mining and Mineral Processing. University of Queensland 2007: 516.
  2. Alipenhani B, Bakhshandeh Amnieh H, Majdi A. Physical model simulation of block caving in jointed rock mass. International Journal of Mining and Geo-Engineering. 2022; 56 (4): 349–359. https://doi.org/10.22059/IJMGE.2022.339663.594953
  3. Alipenhani B, Bakhshandeh Amnieh H, Majdi A. Application of finite element method for simulation of rock mass caving processes in block caving method. International Journal of Engineering, Transactions A: Basics. 2023; 36(1): 139–151. https://doi.org/10.5829/IJE.2023.36.01A.16
  4. Alipenhani B, Majdi A, Bakhshandeh Amnieh H. Determination of caving hydraulic radius of rock mass in block caving method using numerical modeling and multivariate regression. Journal of Mining and Environment. 2022; 13 (1): 217–233. https://doi.org/10.22044/jme.2022.11589.2149
  5. Rice GS. Ground movement from mining in Brier Hill mine, Norway, Michigan. Proceeding of American Institute of Mining and Metallurgical Engineers, vol. 109, American Institute of Mining and Metallurgical Engineers. 1934; 118–152.
  6. Panek LA. Subsidence in undercut-cave operations, subsidence resulting from limited extraction of two neighboring-cave operations. Geomechanical Appli-cations in Hard Rock Mining. 1984: 225–240.
  7. Ross I, Van AA. Northparkes Mines-design, sudden failure, air-blast and hazard management at the E26 block cave. 9th AusIMM Underground Operators Conference 2005, Australasian Inst Mining & Metallurgy. 2005; 7–18.
  8. Carlson G, Golden R. Initiation, Growth, Monitoring and Management of theCave at Henderson Mine A Case Study. 5th International Conference and Exhibition on Mass Mining. 2008; 9: 97–106.
  9. Beck DA, Sharrock G, Capes G. A coupled DFE-Newtonian cellular automata cave initiation, propagation and induced seismicity. 45th US Rock Mechan-ics/Geomechanics Symposium, ARMA; 2011; 9.
  10. Fu Y, Song X, Xing P. Study of the mining height of caving zone in large mining height and super-long face of shallow seam. Journal of Mining & Safety Engineering. 2010; 27: 190–194.
  11. Song XM, Gu TF, Yan ZH. Effects of increasing working face’s length on underground pressure behaviors of mining super-high faces under shallow coal seam. Chinese Journal of Rock Mechanics and Engineering. 2007; 26: 4007–4012.
  12. Xu JL, Zhu WB, Wang XZ. New method to predict the height of fractured water-conducting zone by location of key strata. Journal of China Coal Society. 2012; 37: 762–769.
  13. Teng Y, Tang Z, Zheng Z. Research and Application of Surface Subsidence Law of Fully-Mechanized Top Coal Caving. China Coal Industry Publishing House, Beijing 2009.
  14. Majdi A, Hassani FP, Nasiri MY. Prediction of the height of destressed zone above the mined panel roof in longwall coal mining. International Journal of Coal Geology. 2012; 98:62–72. https://doi.org/10.1016/j.coal.2012.04.005
  15. Someehneshin J, Oraee-Mirzamani B, Oraee K. Analytical model determining the optimal block size in the block caving mining method. Indian Geotechnical Journal. 2015; 45: 156–168. https://doi.org/10.1007/s40098-014-0119-1
  16. Xia ZY, Tan ZY. Study on Instability Mechanism of Extraction Structure under Undercut Space Based on Thin Plate Theory in Block Caving Method. Shock and Vibration. 2021:11: 5548213. https://doi.org/10.1155/2021/5548213
  17. Zhou Z, Cao J, Lai L, Zhou J, Xu M. Determination of the Caving Zone and Fracture Zone Heights by Using the LK-Means Algorithm. Advances in Civil Engineering. 2023; 5119602. https://doi.org/10.1155/2023/5119602
  18. Zhang Q, Guo J, Lu X, Ding K, Yuan R, Wang D. Simulation and On-Site Detection of the Failure Characteristics of Overlying Strata under the Mining Disturbance of Coal Seams with Thin Bedrock and Thick Alluvium. Sensors. 2024; 24(6): 1748. https://doi.org/10.3390/s24061748
  19. Alipenhani B, Jalilian M, Majdi A, Bakhshandeh Amnieh H, Khosravi MH. Determination of the caving zone height using numerical and physical modeling based on the undercutting method, joint dip, and spacing. Journal of Mining and Environment. 2024; 15 (4): 1539–1562. https://doi.org/10.22044/jme.2024.13984.2609
  20. Sainsbury BA. A model for cave propagation and subsidence assessment in jointed rock masses. PhD Thesis. UNSW Sydney, 2012.
  21. Peng S. Surface subsidence engineering: Theory and practice. CSIRO Pub-lishing; 2020.