CENTRIFUGE MODEL STUDIES OF SALT BACKFILL

This paper presents a study developed to assess the potential use of s alt tailings as backfill to control surface subsidence and as a mine b ulkhead used to isolate areas of potential brine inflows. A series of index tests, centrifuge model tests and quasi-static creep-consolidati on tests were performed to evaluate the creep and consolidation proper ties of salt backfill and-to evaluate the effect of brine inflow and b rine infiltration on backfill behaviour The centrifuge models were spe cifically designed to study the mechanical behaviour of salt backfill under the influence of brine inflow and long-term creep. Test results indicated that salt tailings could be applied underground as a bulkhea d to seal off areas of potential inflow with the additional advantage of controlling room closure and local back instability. It is hoped th at this study will assist mine planners to develop contingency plans t o control brine inflow occurrences.