Influence of Chemical Admixtures on Properties of Alkali-Activated Slag-Based Mortars

E-ISSN： 1662-8985|2015|1124|37-42

ISSN： 1022-6680

Source： Advanced Materials Research, Vol.2015, Iss.1124, 2015-10, pp. : 37-42

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

Alkali-activated slag (AAS) based binders can have similar or even better properties in terms of mechanical performance, durability and chemical resistance than ordinary Portland cement (PC), but AAS binders also show some drawbacks, especially high shrinkage and poor rheology. Improvement of these features in the case of PC binder is well established, but a lot of conventional admixtures like superplasticizers do not work in AAS. The influence of shrinkage reducing admixture (SRA) and airentraining admixture (AEA) on mechanical properties, workability and shrinkage was investigated in this study. These admixtures were used in the different dosages in the range of 0–2.0% (by mass of slag). With increasing content of both admixtures compressive and flexural strength decreased. Similar effect was observed for workability. On the other hand, promising results in respect of shrinkage reduction were obtained particularly for SRA, where its 1.0% dose reduced drying shrinkage of the reference mortar by more than 70%. Only slight shrinkage reduction was observed for 0.50% of AEA.