Table 3 summarizes the technical specifications and acceptance criteria for shotcrete at the mine. 2.2 On-site batching and application The mine set up a mobile wet-shotcrete system to enable timely delivery of material to the headings. A colloidal mixer and trans-mix truck were used to batch the new mix underground near the working areas, ensuring fresh concrete was available shortly after each blast. The use of a wet-mix process (as opposed to dry-mix shotcrete with bagged material) improved consistency and reduced dust and rebound. Shotcrete was applied using a robotic spraying unit (track-mounted sprayer) for efficient coverage and to minimize manual work at the face. Immediately after a round was blasted and mucked out (and any required scaling was performed), the spraying unit would move in to apply a layer of fiberreinforced shotcrete to the freshly exposed walls and backs. Typical application thickness was 50–75 mm of shotcrete over the surface, which was deemed sufficient as primary support in these conditions alongside rock bolts. Notably, the introduction of ICS allowed some modification of the support sequence: fiber shotcrete was applied prior to installing
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