Durability of Concretes Containing Supplementary Cementing Materials Under Hot and Aggressive Environment

摘要

It is well known that supplementary cementing materials can enhance the durability of concrete structures particularly in the hot and severe environment. In this study, concrete specimens containing different supplementary cementing materials, namely; silica fume, slag, a natural pozzolan (trass), and mixtures of cement and two pozzolans have been investigated. The tests conducted include, compressive strength, permeability, chloride diffusion, corrosion of reinforcing bars, and carbonation depth, all at different ages. The variables were cement types, supplementary cementing materials, water-cement ratio, and cover thicknesses. After standard curing, concrete specimens were transferred to the Gulf region and maintained in submerged, wetting and drying and coastal environments. For exposure to alternate cycles of wetting and drying, known as the most severe condition, the superior performance of silica fume was followed by the concrete mixture containing trass. However, all concrete mixtures containing natural or artificial pozzolans showed better performance compared with the portland cement control concrete mixtures.