Corrosion rate evolution in concrete structures exposed to the atmosphere

The data on corrosion rate values measured on-site in real size concrete structures are scarce, while the data bank of values in laboratory specimens is relatively larger. The majority of the experiments in the laboratory have been performed in chambers of controlled relative humidity and temperature, however real outdoor climate usually is characterized by day–night and seasonal temperature cycles. These cycles, or natural weathering, influence the internal relative humidity of the concrete and the corrosion rate of the steel. In the present paper, results of corrosion rate of steel in chloride containing concretes exposed to natural weathering, are presented.