Optimising fibrecrete for deep shaft support: lessons from the Wira Shaft sink

Authors: Coad, R; Chadbourn, G; Hill, C; Lagacé, D Download Paper

DOI https://doi.org/10.36487/ACG_repo/2625_14

Cite As:
Coad, R, Chadbourn, G, Hill, C & Lagacé, D 2026, 'Optimising fibrecrete for deep shaft support: lessons from the Wira Shaft sink', in D Cumming-Potvin & J Wesseloo (eds), Ground Support 2026: Proceedings of the 11th International Conference on Ground Support in Mining, Australian Centre for Geomechanics, Perth, pp. 1-14, https://doi.org/10.36487/ACG_repo/2625_14



Abstract:
In shaft construction, achieving rapid and reliable ground support is critical to safety and productivity. This paper presents the development and implementation of a high-performance fibrecrete mix tailored for use as the primary temporary ground support element in the Wira Shaft at Prominent Hill Mine, South Australia. Engineered for early strength gain and optimised for slickline delivery, the mix incorporated high cement content, steel fibres, and admixtures to overcome challenges in pumpability, workability retention, and application consistency. Comprehensive testing, including workability, early and late age compressive strengths, and LiDAR-based thickness mapping, were conducted across more than 1,200 m of shaft. Operational learnings, such as the impact of deleterious fines, admixture handling, and fibre selection, informed real-time adjustments and long-term recommendations. This paper provides practical insights for future fibrecrete only support regimes, emphasising the importance of quality control and assurance, operator training, and material control in achieving safe and efficient shaft sinking.

Keywords: shaft sinking, fibrecrete, early-age strength, quality control, slickline delivery

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