chapter  4
60 Pages

Heat and humidity

Although cemented backfill is an important source of heat, no studies concerning its contribution and effect have been produced. Under certain circumstances, cemented backfill may become a critical source of heat. Mines operating in the high arctic for example, operate in permafrost ground conditions. Although frozen rock exhibits superior strength and demonstrates low susceptibility to ground disturbance, mining development may result in thawing of the rock mass due to heat transfer, with subsequent reduction in rock strength. A number of such mines use frozen backfill as a means of ground support, whilst some have employed cemented backfill when secondary filling is required. Under such circumstances, heat produced from cemented backfill, if not controlled, may adversely affect the integrity of such mines. As the thaw front advances into joints and fractures in the rock mass, reduction in rock strength would result, thus compromising the stability of the workings.