Safety of barricades in cemented paste-backfilled stopes

Abstract

In underground mining, there has been an increasing use of “cemented paste” for the backfilling of stopes. As this cemented paste backfill (CPB) enters the stope as a fluid, shotcrete barricades are often used to retain the fill material during and after the filling operations. However, failures of barricades have been reported around the world in recent years. This paper presents an analytical solution based on the elastic thin plate theory for calibrating the design of shotcrete barricades in underground mines using CPB. This solution was used to determine the quantitative relationships between the lateral loading from the paste and the barricade response during the backfilling process. The results show that the proposed solution agrees well with in situ data. According to the actual barricade responses, the acceptable tensile stress and an analysis method of cracks development are proposed. The proposed solution has practical significance for underground mines.

Keywords

cemented paste backfill / barricade / elastic thin plate theory / mine safety / in situ measurement

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