ABSTRACT
As part of a research program on the influence of supplementary cementing materials on the deicer salt scaling resistance of concrete, thirteen different mixtures were prepared and tested. The variables tested were the cement (two ordinary Portland cements originating from two different plants were used), the type of supplementary cementing materials (two class F fly ashes and one slag were used) and the curing period (the concretes were tested after 14 and 28 days of normal curing). All mixtures were prepared at a constant water/binder ratio of 0.40, and all scaling tests were carried out on troweled surfaces. The results indicate that the use of supplementary cementing materials generally has a negative influence on the deicer salt scaling resistance of concrete, and that the extension of the curing period from 14 days to 28 days does not significantly increase the scaling resistance. Furthermore, the variation of the mass of scaling residues with the number of cycles indicate that the rate of deterioration of the concretes containing fly ash or slag is more rapid during the first cycles, suggesting that the use of supplementary cementing materials affects the microstructure of the surface layers.
