ABSTRACT
The term “final lining shotcrete” means different things to different people, especially when one considers the differences between civil and mining applications. Notwithstanding that, a common link from all perspectives involves the application of shotcrete for durable, permanent support in an underground opening. Recent applications in North American tunnels have highlighted the flexibility and economy of this material/process, reducing the in-place cost of ground support systems, and ultimately impacting on the overall viability of projects, especially where infrastructure rehabilitation is concerned. While other parts of the world have led the charge to final lining shotcrete, it is now gaining rapid acceptance in North America and promises benefits for the plethora of underground construction slated over the next decade. A move to wet-mix shotcrete, driven largely by developments in admixture, equipment, fiber reinforcement, and logistical technology, has facilitated a much greater and widespread usage of shotcrete as a primary ground support system, and by extension, as a component of final linings, in North American underground mines. Aside from benefits in speeding up the development cycle, and improving overall economics, a dramatic decrease in injuries due to ground falls and other downstream advantages are revealing the potential for shotcrete as an essential tool for competitive mining in the new milennium. This paper will expand on the concepts summarized above, and illustrate them with recent case studies.
