Resistance to chemical attack of bittern-resisting cement in high-bittern environment
摘要
A new kind of bittern-resisting cement (BRC) was introduced. This material is based on the ternary cementitious system of clinker containing C4A3 -S phase, high-activity ground granulated blast-furnace slag (GGBFS) and fly ash (FA). The hydration process and the hydrated products of BRC were studied by means of XRD, TG-DTA and SEM, and the resistance to chemical attack of BRC in high-bittern environment was also examined. The corrosion experiment in seven kinds of brines proved that BRC exhibits an excellent resistance to chemical attack of bittern. The corrosion resistance factors were calculated and all of them were greater than 0.96. It showed that BRC totally controls the cement-based material corrosion in brines from four aspects: (1) making full use of the dominant complementation effect of mineral materials; (2) diminishing the hydrated products easy to be attacked; (3) improving the microstructure of hardened cement mortar; (4) degrading the chemical attack of bittern.