EFFECTS OF ADDITIVES ON THE HYDRATION AND HARDENING OF SULFOALUMINATE CEMENT (SAC) AND THE CORROSION RESISTANCE OF ITS MORTAR

Abstract

Despite various excellent properties, sulfoaluminate cement (SAC) can meet special engineering needs only after its properties are regulated using additives. In this study, the effects of aluminium sulfate single-doping, boric acid single-doping, and boric acid-polycarboxylate superplasticiser co-doping on the hydration rate, mechanical properties, chloride penetration resistance, and sulfate corrosion resistance of SAC and its mortar were explored. The results revealed that aluminium sulfate accelerates the hydration of SAC, and the boric acid single-doping and boric acid and polycarboxylate superplasticiser co-doping both delay the hydration of SAC, which is especially delayed by the latter; the mechanical properties, chloride penetration resistance, and sulfate corrosion resistance of the mortar are always sorted as boric acid and polycarboxylate superplasticiser co-doped samples>boric acid single-doped samples>aluminium sulfate single-doped samples, which is closely related to their effects on the crystal size and matrix compactness of the cement hydration products.

Keywords

• sac
• hydration
• compressive strength
• chloride penetration resistance
• sulfate corrosion resistance