SGIS – Četrnaesto međunarodno naučno-stručno savetovanje „Ocenja stanja, održavanje i sanacija građevinskih objekata“ (2026) [23-34]
AUTHOR(S) / АУТОР(И): Zlatko Zafirovski 
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DOI: https://doi.org/10.46793/SGIS26s.023Z
ABSTRACT / САЖЕТАК:
This paper presents the assessment of the existing condition and the proposed rehabilitation methodology for the hydro-technical bypass tunnel located beneath the Sasa tailings dam in North Macedonia. The tunnel plays a crucial role in safely diverting the Kamenicka Reka watercourse and ensuring the operational safety of the tailings facility. Inspections conducted up to 2025 revealed significant deterioration of the concrete lining, including hydro-abrasive erosion, reinforcement corrosion, water infiltration, and structural cracking. These defects have adversely affected both the hydraulic performance and structural stability of the tunnel. Based on the identified damage mechanisms, a comprehensive rehabilitation solution was developed, including substrate preparation, reinforced wet-mix shotcrete application, anchoring systems, drainage measures, and protective surface treatment. The proposed intervention aims to restore the tunnel’s structural integrity, improve hydraulic efficiency, and extend its service life under aggressive conditions. The presented methodology provides a practical approach for the rehabilitation of similar hydro-technical structures within mining and tailings management systems.
KEYWORDS / КЉУЧНЕ РЕЧИ:
hydro-technical tunnel, rehabilitation, shotcrete, tailings dam, structural assessment, abrasion damage
ACKNOWLEDGEMENT / ПРОЈЕКАТ:
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