Paper contribution

Physical Modeling of Rockfill Material for Construction of Specific Waste Disposals Using a Large-Scale Direct Shear Apparatus

Tamara Jovanovska; Eray Altıncı; Bahadır Başdemirci; Jovan Br. Papić

Proceedings
EUROCK 2026
Pages
355-360
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

This paper presents the preparation and testing of a physical model for large-scale direct shear testing of rockfill material using a shear box with dimensions of 1.0 × 1.0 × 0.6 m. The material, sourced from the Borov Dol mine pit, represents excess rockfill generated during excavation and intended for the mine’s waste dump area. The applied normal stress is generated by four vertical hydraulic presses with a total capacity of 1 MPa, while the horizontal shear load is applied using two inclined hydraulic presses positioned at an angle of approximately 11° relative to the horizontal plane. The lower frame of the apparatus is static, and the upper frame moves during shearing. Mixtures of fresh and altered andesitic rock, as well as their combinations, were tested. Results show that higher proportions of large blocks increase the internal friction angle. The influence of fine particles, intact rock strength, and surface roughness on shear behavior was also examined. The obtained data were compared with the Hoek–Brown and Barton strength criteria to support the development of a simplified approach for rapid extrapolation of large-scale test results.

Contributors

Authors

  1. Tamara Jovanovska Ss. Cyril and Methodius University in Skopje; Geodestek Ltd. Şti. ORCID 0000-0002-9703-2206
  2. Eray Altıncı Geodestek Ltd. Şti.
  3. Bahadır Başdemirci Geodestek Ltd. Şti.
  4. Jovan Br. Papić Ss. Cyril and Methodius University in Skopje ORCID 0000-0002-2952-302X

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References

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