Supplementary cementitious materials (SCMs), that is, slag, fly ash and silica fume, are now recognised as an integral part of concrete technology and construction, due to their ability to enhance the properties of fresh and hardened concrete. Since their introduction in 1993 into the VicRoads concrete specification, a number of major structures have been successfully constructed utilising these cement replacement materials. An investigation was undertaken to evaluate their suitability under various curing regimes, including moist curing, polyethylene sheeting, curing compounds and wet/dry curing. The study has confirmed previous research results in that the use of SCMs in concrete results in significant reductions in the volume of permeable voids (VPV). The greatest VPV reductions occurred in concrete containing moderate single combinations of silica fume followed by fly ash and finally slag. Based on the efficiencies of the curing techniques with respect to strength development and VPV reduction, it has been recommended that polyethylene sheeting and curing compounds not be allowed for curing of concrete with high replacement of SCMs. (a)
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