Reaction products, structure and properties of alkali-activated metakaolin cements incorporated with supplementary materials – a review

Incorporation of mineral blending and/or modifying additions which are single- or multi-component materials is one of the main trends in the development of both Portland clinker-based and non-clinker cements. There is an increasing scientific and industrial interest in alkali-activated binders as ecologically and technically promising inorganic materials. Progress in this area is also derived from advances in the technologies of production and processing of a wider range of mineral materials from natural and waste origins, and by constant expansion of the raw materials base of alkali-activated materials. This paper reviews (i) alkali-activated metakaolin-based cements incorporated with mineral supplementary materials from the point of view of the supplementary additions raw materials base, features of reaction products, structure, properties and formation process; (ii) a range and classification of mineral additions to alkali-activated metakaolin cements; (iii) the feasibilities of improving the structure and properties of mixed alkali-activated metakaolin cements. Keywords: Metakaolin, Slag, Fly ash, Alkali activation