Durability of steam-cured concrete with slag under the combined deterioration of freeze-thaw cycles and de-icing chemicals

In previous studies of the durability of concrete containing slag exposed to the combined impact of de-icing chemicals and freeze-thaw cycles, the scaling resistance of concrete was improved by using slag replacement amounts ranging from 25 to 35% of the total cement content. However, the resistance decreased rapidly when the amount of slag replacement increased beyond 40% of the cement content. Furthermore, in these studies, only normally cured concrete products were used rather than steam-cured concretes. Thus, the research on the scaling resistance of steam-cured concrete products with slag replacement has not been studied enough. In this study, the durability characteristics of steam-cured concrete containing slag exposed to the impact of concrete de-icing chemicals and freeze-thaw cycles were investigated with the aim of improving the quality of precast concrete products. Scaling, chloride ion penetration, pull-off strength and the relative dynamic modulus of elasticity were evaluated for both the pouring and bottom surfaces of the specimens. This was done because it was expected that the concrete pouring surface would suffer more degradation than the bottom surface owing to weakened concrete strength caused by bleeding effects.