2013 W.R. Whitney Award Lecture: Probabilistic Treatment of the Reinforcement Corrosion

Concrete, together with the steel and reinforced by it, is the most widely used building material. Its site fabrication and diverse performances introduce an enormous variability in its composition and properties. Regarding the embedded reinforcing steel, its alkaline nature provides a protection for hundreds and thousands of years; however, chlorides or the concrete pH neutralization may induce active corrosion, which aims to disrupt the rebar passivity and decrease the structural load-bearing capacity. Numerous aspects at present are studied related to reinforcement corrosion in concrete and its prevention and repair. The present paper focuses on the need to develop basic probabilistic treatment for the design of new structures or to assess present conditions of the existing ones. Because of the numerous uncertainties related to the environment and concrete aging, when trying to project the performance to 50 years and 100 years and beyond, the best seems to introduce the principles of reliability analysis to calculate the probability of corrosion and failure, and from that. to establish safety factors that could be incorporated into the design codes. Corrosion and failure risks can then be incorporated into codes of practice of structural concrete.