Model studies on cemented tailings used in mine backfill

Abstract

Physical model tests on cemented classified tailings and sand backfills have been carried out to determine the strength requirements for stability when vertical fill faces are exposed. The results of this laboratory scale model testing support a three-dimensional analytical solution developed in the paper, whereby the cement strength requirement can be reduced when rock walls are sufficiently close together to help support the backfill by shearing stresses at the wall–backfill contact.Comparisons with conventional backfill strength design approaches show that substantial reductions in cement usage can be realized by using the three-dimensional design approach, particularly when blast hole stoping can be carried out to heights several times greater than the lateral stoping dimensions.Physical modelling of cemented backfills is discussed in detail in the paper and it is concluded that field scale model testing could be useful in the design stages of the development of mining methods at individual mines.