SULFATE ATTACK AND REINFORCEMENT CORROSION IN PLAIN AND BLENDED CEMENTS EXPOSED TO SULFATE ENVIRONMENTS

The extensive use and addition of mineral admixtures and the recent mo difications in the physico-chemical characteristics of portland cement s have introduced a large number of variables that need to be addresse d. Furthermore, the effect of cations associated with sulfate ions on these variables is inconclusive and extensively debated in the literat ure. On the other hand, the exposure of many reinforced concrete struc tures to sulfate-bearing environments has brought attention to the rol e of sulfate ions in the corrosion of reinforcing steel. Unfortunately , there is very little data on this aspect. The following subjects are addressed: (i) the effect of sulfate cation type on strength and expa nsion; (ii) the role of sulfate ions in reinforcement corrosion; (iii) the role of plain and blended cements in both sulfate attack and rein forcement corrosion; and (iv) a comparison of the performance of concr ete made with the above-cited cements with that of small (25 mm cube) cube mortar specimens. (C) 1997 Published by Elsevier Science Ltd.