Determination of the Caving Zone Height using Numerical and Physical Modeling based on the Undercutting Method, Joint Dip, and Spacing

Alipenhani, Behnam; Jalilian, Mehran; Majdi, Abbas; Bakhshandeh Amnieh, Hassan; Khosravi, Mohammad Hossein

doi:10.22044/jme.2024.13984.2609

Document Type : Original Research Paper

Authors

¹ School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.

² Department of Mining Engineering, Faculty of Engineering, University of Birjand, Birjand, Iran

https://doi.org/10.22044/jme.2024.13984.2609

Abstract

The paper presents the effect of the dip of joints, joint spacing, and the undercutting method on the height of the caving in block caving. The obtained results show that among the three investigated parameters, respectively, the dip of joints, undercutting method, and joint spacing have the greatest effect on increasing the height of the caving zone. Comparing the data obtained from physical and numerical modeling shows a 97% match. Also, by increasing the joint spacing from 4 to 6 cm, 14%, from 6 to 8 cm, about 35%, and from 8 to 10, about 50%, the height of the caving zone has decreased. Regarding the dip of the joint, with the dip increasing from 30 to 45 degrees, about 3% of the caving height decreases. By increasing the dip of the joint from 45 to 60 degrees, the caving height has decreased by 42%. By increasing this value from 60 to 75 degrees, the caving height has increased by 50%. Also, changing the undercutting method from symmetric to advanced undercutting has increased the caving height by 40%. Additionally, three mathematical models have been proposed based on the shape of the caving zone in physical modeling.

Keywords

Main Subjects

Underground Mining

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Determination of the Caving Zone Height using Numerical and Physical Modeling based on the Undercutting Method, Joint Dip, and Spacing

References

References

Volume 15, Issue 4October 2024Pages 1539-1562

Volume 15, Issue 4
October 2024
Pages 1539-1562