| Steam curing is often used in the production of precast concrete. The elevated temperature of steam curing increases the initial rate of strength development allowing for earlier removal of the formwork. Although elevated curing temperatures result in high early strength, long-term strength and durability may be adversely affected. In this study, the chloride penetration resistance of steam-cured concretes containing silica fume alone or in combination with slag was investigated. The water to cement ratio was kept constant, at 0.3, for all concretes. Testing included: (1) Compressive Strength, (2) Rapid Chloride Permeability, (3) Water Sorptivity, (4) Bulk Diffusion, and (5) Chloride Migration. For a given mixture, steam curing was found to decrease chloride resistance. However, the use of supplementary cementing materials significantly reduced the negative effects of steam curing. The performance of a 4% silica fume steam-cured concrete was comparable to that of a 100% OPC ambient-cured concrete. |
