Effect of condensed silica fume on steel corrosion in concrete

In this paper, current experience is reviewed on how the presence of condensed silica fume (CSF) may affect the electrolytic conditions in concrete and, hence, the ability of concrete to protect embedded steel against corrosion. Even in the presence of large amounts of CSF; the passivity of embedded steel will riot be destroyed. Decreased permeability will reduce the rate of carbonation. In a chloride-containing environment, resistance to chloride penetration will be substantially increased. Oxygen availability will not be affected much. However, even if passivity becomes broken, either by carbonation or by penetrating chlorides, the electrical resistivity may be so high that steel corrosion will nor represent any practical problem. If properly dispersed CSF is combined with a low water-cement ratio and proper curing, it appears that concrete structures with an excellent performance can be constructed even in the most aggressive and hostile environment.