Effect of fly ash and early strength agent on the sulfate resistance of concrete

Based on the testing of mass loss rate, chloride ion diffusion coefficient and compressive strength, as well as the microcosmic analysis of SEM and EDS, effects of fly ash and the early strength agent of sodium sulfate on the damage of concrete exposed to the cyclic sulfate environment are studied. The results show that incorporation of fly ash decreased the initial chloride ion diffusion coefficient and compressive strength of concrete, and promoted the compressive strength loss of concrete subjected to the cyclic sulfate exposure. Incorporation of the early strength agent of sodium sulfate decreased the initial chloride ion diffusion coefficient of concrete and increased its initial compressive strength, reducing the compressive strength loss of concrete exposed to the cyclic sulfate environment.