Durability of concrete exposed to sulfate attack under flexural loading and drying–wetting cycles

The damage process of concrete exposed to sulfate attack under flexural loading and drying–wetting cycles are investigated in this paper. ESEM, MIP, and XRD were used to investigate the changing of microstructure and corrosion products of interior concrete. The results indicate that compared with the single damage process of sulfate attack, flexural loading and drying–wetting cycles can both accelerate the damage process of concrete subjected to sulfate attack. While compared with sulfate attack and drying–wetting cycles, the effect of flexural loading on the deterioration of concrete depends on the stress level. It was also found that the addition of admixtures can improve the ability of sulfate resistance of concrete when it is also subjected to mechanical loading and drying–wetting cycles.

► Durability of concrete exposed to sulfate under drying–wetting cycles and load is studied.
► The microstructure of interior concrete are determined by using ESEM, XRD, and MIP.
► Load and drying–wetting cycles can both accelerate the sulfate corrosion of concrete.
► The effect of load on the damage of concrete under combined actions depends on the ratio.