Paper contribution

Stability Analysis and Support Design for the Deepening of the Main Shaft in the Trepça Mine, Kosovo

Gzim Ibishi; Melih Genis; Mahmut Yavuz; Arjanit Ademi

Proceedings
EUROCK 2026
Pages
971-976
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

In this paper, the stability analysis and preliminary support design for the Trepça main shaft deepening are addressed, thereby enabling the opening of new horizons (i.e., mining levels). Field investigations and rock mass classification systems (e.g., RMR, RMQR) indicate that the breccia, schist, and limestone rock masses along the shaft excavation exhibit stability problems, necessitating an optimal supporting structure. Using the finite element numerical method, the performance of the support systems recommended by the empirical methods was successfully evaluated. The numerical analyses and results showed that the empirical methods are not always valid and fail to investigate the performance of the supporting deep structures for weak and very weak rock masses. In this study, a series of numerical analyses was performed to evaluate different possible support scenarios. Accordingly, for three main different geological lithologies (e.g., breccia, schist, limestone), an optimal support system is proposed, with a concrete lining thickness ranging from 30 to 50 cm with concrete class C25 and C30. Consequently, satisfactory results were obtained and analysed with respect to total displacements and the thickness of the plastic zone.

Contributors

Authors

  1. Gzim Ibishi Mitrovica Isa Boletini University, Kosovo ORCID 0000-0002-1160-3881
  2. Melih Genis Zonguldak Bulent Ecevit University, Turkiye ORCID 0000-0002-2990-9707
  3. Mahmut Yavuz Eskisehir Osmangazi University, Turkiye ORCID 0000-0001-6215-8557
  4. Arjanit Ademi Trepça Joint Stock Company, Mine and Flotation Trepça, Stantërg, Kosovo

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References

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  9. Unsupported
  10. Supported
  11. Support capacity diagram(s)
  12. Plastic zone Rpl/R
  13. Breccia (H = 800 m)
  14. Total displacement (mm)
  15. Plastic zone Rpl/R
  16. Schist (H = 860 m)
  17. Total displacement (mm)
  18. Plastic zone Rpl/R
  19. Limestone (H = 930 m)
  20. Total displacement (mm)
  21. Fig. 2 Numerical model results for shaft deepening along breccia, schist, and limestone rock masses.