ABSTRACT
Historically, strength development in underground backfill is estimated based on the results of historic unconfined compressive strength (UCS) testing. During both preliminary study phases and operational phases are batched to specific solids and binder contents and placed in curing chambers, with the intention that these chambers replicate the curing conditions experienced underground.
The rate of strength development in mining backfill can be greatly affected by variations in environmental factors including temperature & humidity. Therefore accurate representation of in situ curing conditions for cemented specimens is crucial.
This paper investigates the effect that differing curing conditions can have on the strength development of cemented mine backfill specimens. This paper explores how variations expected to be encountered in typical fill masses impacts the resulting strengths and also investigates how aspects that may appear subtle can actually have a significant impact on the resulting measured strengths. Given the findings of this investigation a series of recommendations are provided for improving the way mine backfill curing chambers are managed.
