Effect of admixture on sulfate resistance of alite-barium calcium sulphoaluminate cement mortar

The effects of slag as single or compound admixture on the sulfate resistance of alite-barium calcium sulphoaluminate cement were studied. The results indicated that the addition of slag restrained the formation of ettringite and gypsum due to the activation effect of alkali and sulfate in alite-barium calcium sulphoaluminate cement, and the suitable mass fraction of slag was 20%. The corrosion resistant coefficient of cement added slag and limestone reduced obviously, while the negative influence of limestone was diminished by the presence of the slag. When the blend of slag and fly ash were contained in the cement, the optimum combination was 30% slag and 20% fly ash. By comparison, adding slag singly in the cement leads to the best behavior with respect to the sulfate resistance.