Study on water resistance modification of magnesium oxysulfate cement

Abstract

Large-scale applications of magnesium oxysulfate (MOS) cement in civil engineering have been restricted by its defects such as low early strength and poor water resistance. In this study, some additives were used to modify MOS cement. The results show that phosphoric acid and citric acid can effectively increase the mechanical strength of MOS cement with the dosage of 0.6% and 0.3% respectively. The addition of fly ash and waste GFRP fiber contribute little for the mechanical strength of MOS cement, but has positive effect on water resistance improvement. Silica fume can significantly improve the mechanical of properties and water resistance of MOS cement as well.