Backfill is the only form of regional ground support. As such, it is essential in underground mining, with special relevance to deep and high stress mining. For hydraulic and paste backfills, barricades must be constructed to retain the initially fluid backfill. The most common engineered barricade designs feature arched reinforced concrete panels. In this paper we argue that essentially unreinforced arched barricades are feasible and in many cases are optimal from logistical and cost perspectives. We begin with a case study of a flat reinforced barricade that was subjected to an extended period of fluid loading. The theoretical advantages of unreinforced arched barricades are then investigated. Both uniform and non-uniform thickness arches are considered, as well as the relative influence of the surrounding rock mass that provides the “foundations” to the arched barricade. Finally, the importance of instrumentation in backfill cannot be understated. Mines can use simple pressure measurements to verify loading assumptions (i.e., during plug pour, and plug cure periods) and in advanced cases, use such measurements to identify “safe” loading conditions (with respect to the barricade capacity) and accelerate backfilling, with potentially significant effect on stope cycle times.
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