Some Aspects of Reinforcement Corrosion in Egyptian Structures

Abstract

Three deteriorated structures exposed to different environmental conditions in Egypt and a non-deteriorated structure have been inspected. Visual and microscopic examination of reinforcing steel samples from the different constructions revealed the occurrence of pitting corrosion in the reinforcement of a building exposed to a marine atmosphere, local and general attack in the reinforcement of a Filtration Building for the Domestic Water Project and stress corrosion cracking in the horizontal reinforcement of some concrete columns of a building made of Portland blast furnace slag cement. It has been found that the type of corrosion is mainly determined by the type of aggressive ions present in the concrete and ta a lesser extent by the microstructure of steel. Examination of the non-deteriorated structure led to the conclusion that low concentrations of aggressive ions in, and high alkalinity of, the concrete, relatively low C and S contents of the reinforcement and a non-aggressive surrounding atmosphere establish the ideal conditions for the durability of the structure.