The requirement for rapid vertical development for underground ventilation is often a factor when dealing with dynamic mine plans, with short vertical developments being used to optimise ventilation systems. In an effort to increase the safety and efficiency of the constructions, a simple and effective sinking methodology is required that is both adaptable and repeatable. A modified shaft construction methodology is proposed that attempts to minimise risk to the personnel as well as be cost-effective. Readily available equipment is used to ensure adaptability to the various environments and shaft parameters. One of the greatest risks of shaft sinking is having personnel working suspended over open cavities or underneath suspended loads. Removing this risk, by ensuring all construction is done from solid ground, allows for safer sinking operations. As the process is repeatable, familiarity and confidence in its construction sequence will increase with each successive sink. A trial sink is performed with a 3.6 m diameter, 20 m deep shaft. The shaft was excavated using a conventional strip-and-line philosophy, with the shaft then being lined from the collar via the use of large diameter corrugated steel culverts. The annulus between the steel culverts and shaft excavation is then filled with a concrete mixture to secure it in position. The new process was successful, with no personnel at any time during the process being suspended above an open excavation. The installation had relatively low capital and operational costs and was completed faster than an equivalent, conventional concrete-lined shaft construction. Therefore when compared to conventional shaft-sinking methods, this process can be considered safer, more efficient and relatively cost-effective. Further research is required to determine whether this method can be expanded to larger vertical developments.
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