The Effect of Curing Temperature and Supplementary Cementitious Materials on Chloride Permeability of Self-Compacting Concrete

In recent years, self-compacting concrete (SCC) has gained popularity due to its high flowability and reduced energy demand in construction. With a notable paste content, SCC undergoes intensified hydration reactions, resulting in a distinct microstructure compared to traditional concrete. When exposed to varying curing temperatures, SCC exhibits unique mechanical traits. However, the influence of curing temperature on SCC with supplementary cementitious materials (SCMs) remains underexplored. This study evaluates SCC performance with diverse SCMs, substituting specific volume fractions of cement with 10% silica fume (SF) and 40% fly ash (FA), under different curing temperatures. Emphasis lies on assessing the durability of these compositions for concrete structures. For evaluating critical chloride permeability, high-strength SCC specimens were cured underwater at 10 °C, 20 °C, and 50 °C. Incorporating supplementary cementitious materials (SCMs) enhances SCC's resistance to chloride permeability and mitigates the adverse effects of elevated curing temperatures. The study showcased remarkable enhancements in concrete performance with the addition of silica fume (SF) and fly ash (FA) compared to plain SCC. Particularly, at 10 °C, SCC with SF exhibited a significant increase rate of 78.89% over SCC without SF. These results underscore the pivotal role of SF and FA in bolstering the electrical resistance of SCC under different curing temperatures.