Some aspects of alkali-activated slag binders durability

Alkali-activated slag (AAS) binders are cementitious materials based on compositions in the Me2O-MeO-Me2O3-SiO2-H2O system. Such binding materials have a great potential for using industrial by-products in chemically bonded ceramics. High mechanical strength, low hydration heat and good resistance to chemical attack are typical for alkali-activated slag binders. Long-term resistance (5 years) of AASC and OPC mortars in magnesium sulphate and chloride solutions was measured. The results obtained show very good durability of AAS mortars compared to OPC mortars. High durability of AAS mortars and concretes is determined by phase composition of the hydration products (high content of C-S-H phase with low C/S ratio), very low porosity and dense interfacial zone AAS paste-aggregate.