Study on the Durability of Silica Fume Concrete in High Sulfate Environment of Plateau

Abstract

AbstractTo investigate the effect of sulfate corrosion on the compressive strength of silica fume concrete under freeze-thaw conditions, different concretes with silica fume contents of 0%, 5%, 10%, and 15% were exposed to dry-wet erosion with 5% sulfate, freeze-thaw cycles with clear water, and dry-wet erosion with 5% sulfate followed by freeze-thaw cycles for a period of 75 days. The changes in compressive strength under different conditions and at different time intervals were analyzed. The results indicate that the extent of strength damage follows the order: dry-wet+freeze-thaw>freeze-thaw>dry-wet. The combined effect of dry-wet+freeze-thaw accelerates the deterioration of concrete strength. As the silica fume content increases, the rate of concrete compressive strength loss gradually stabilizes. For the 0% and 5% silica fume concretes, the loss of strength under the combined effect of dry-wet+freeze-thaw is more pronounced for 60 days. However, as the silica fume content increases beyond 5%, the rate of strength loss decreases by more than 10%. Therefore, the increase in silica fume content leads to a decrease in the rate of concrete strength loss.