Key points are not available for this paper at this time.
Alkali-activated concrete (AAC) is a promising sustainable alternative to cementitious materials concerning its environmental benefits and satisfactory engineering properties. Given the growing use of limestone and other forms of calcium carbonate as an additive or supplementary precursor in AAC, this review summarises the effect of limestone on the engineering properties of AAC synthesised from various precursors such as fly ash, slag, metakaolin, and blends of them. Due to the underlying mechanisms including filler effect, additional nucleation and dilution effect, and chemical reaction of limestone, the incorporation of limestone with physical and chemical modifications into AAC can result in changes in reaction kinetics, microstructure, fresh properties, and hardened properties of AAC, which are quantitatively discussed and compared. In addition, the sustainability and environmental impact of AAC containing calcium carbonate are also assessed, whilst the research gap and opportunities for the future are identified.
Chan et al. (Wed,) studied this question.