Title: Effect of Condensed Silica Fume on Steel Corrosion in Concrete

Author(s): Odd E. Gjorv

Publication: Materials Journal

Volume: 92

Issue: 6

Appears on pages(s): 591-598

Keywords: carbonation; chlorides; corrosion; diffusivity; electrical resis-tance; silica fume.

DOI: 10.14359/9778

Date: 11/1/1995

Abstract:
In this paper current experience is reviewed on how the presence of con-densed silica fume (CSF) may affect the electrolytic conditions in concrete and, hence, the ability of concrete to protect embedded steel against corro-sion. Even in the presence of large amounts of CSF, the passivity of embedded steel will not 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 car-bonation or by penetrating chlorides, the electrical resistivity may be so high that steel corrosion will not 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.