Corrosion of Reinforcing Steel in Concrete In Morine Atmospheres

Abstract

A brief review is given of the corrosion of reinforcing steel in concrete structures exposed to sea water action. The relations of concrete porosity, permeability, strength, water-saturation, and electrical resistivity to the corrosive action are discussed. It is postulated that the existence of macro-galvanic cells in concrete structures are chiefly the result of differential oxygen concentrations in the pore space water. The differences in oxygen concentrations arise from differing oxygen solubilities in pore space water of different concentrations of dissolved sea salts and from lower availability of oxygen in those areas of high water-saturation. The corrosion of the reinforcing steel found in the San Mateo-Hayward bridge is used to illustrate the corrosion mechanism. Recommendations are given for preventing corrosion in new structures and for correcting the problem in existing structures. 6.6.5, 4.6.11, 3.6.2