Investigation of chloride penetration in carbonated reactive magnesia cement mixes exposed to cyclic wetting–drying

The effect of chloride attack on carbonated reactive MgO cement (RMC) samples containing fly ash (FA) and ground granulated blast-furnace slag (GGBS) under cyclic wetting and drying was studied. Porosity, sorptivity and chloride profile observations were carried out in parallel to the XRD, TGA and SEM analyses performed before and after exposure. Inclusion of SCMs increased the resistance of RMC samples by lowering the porosity and leading to the formation of various phases such as bischofite, hydrotalcite and calcite, in addition to Mg-carbonates. Mg-carbonate phases such as hydromagnesite and artinite remained relatively stable, whereas a small reduction in nesquehonite content was observed after exposure. Resulting formulations presented improved durability and lower environmental impacts.