DEVELOPMENT OF MIX DESIGNS FOR STRENGTH AND DURABILITY OF STEAM-CURED CONCRETE

The importance of concrete strength and durability for the satisfactory performance of concrete is noted, and the article describes a study of the optimization of mix designs for concretes subjected to an 18-hour steam curing regime. In all cases, the water-to-cementitious-materials ratio was 0.45, the maximum allowed for a Class A exposure. The details of the materials and mix designs, curing, chloride ion penetration and compressive strength findings are presented. The test results indicated that concretes with such a water/cement ratio can perform very differently, particularly in their resistance to chloride ion intrusion. In the case of steam-cured concretes, silica fume and slag can be used to improve strength and durability. These and other findings are discussed.