Preliminary study on combined-alkali-slag paste materials

This article mainly describes a study on combined-alkali-activated slag paste materials. Without any coarse and fine aggregates, the effect of several factors, such as the kind of alkali, additives, as well as curing conditions on the strength and other properties of the paste materials, has been investigated. The activation of sodium hydroxide shows a better early strength developing than sodium carbonate. However, by using both NaOH and Na2CO3 together at the same dosage, the strength developing shows even better. The most severe problem of the cured paste materials is the shrinkage cracking, which causes the decrease of both flexural and compressive strengths apparently. The effect of several factors is considered and discussed in this paper, hoping to gain a better understanding of the processing of alkali-activated slag solid paste materials. It was shown that there is a good effect of some suitable additives and curing forms on the properties of hardened slag paste materials. (C) 2000 Elsevier Science Ltd. All tights reserved.