Mechanics and safety issues in tailing-based backfill: A review

Abstract

Voids (referred to as “stopes”) are generally created during underground mining activities and can lead to both local and regional geotechnical instabilities. To assist in managing the stability of mining-related voids and improving the recovery of orebodies, tailing-based backfill technology has been widely used around the world. In the design of tailing-based backfill strategy, the specific function and engineering requirements of the filling are intimately dependent on the stress distribution within the backfilled stope. In this paper, the main mechanics involved in tailing-based backfill in underground mines, which include arching, consolidation, hydration process, and movement of surrounding rocks, are reviewed. Research on the safety of a barricade and stability of an exposed fill face are also presented. In conclusion, the back-filling process should be performed on the basis of a better understanding of the complicated interactions of the mechanisms of filling, consolidation, and hydration process (when cement is added).

Keywords

tailing-based backfill / arching / consolidation / barricade / safety

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