Service Life of Concrete during Chloride Ingress

The service life of reinforced concrete infrastructure in a marine environment can be predicted from semi-empirical equations. This work describes what is needed to reliably predict service life of reinforced concrete that is exposed to chlorides and more importantly what “new knowledge” is needed for predicting the service life of concrete cover in the real world. There include; the effect of hydration suction, assumptions about the critical chloride concentration that initiate steel corrosion, flaws in the Fick’s law approach, modifications to paste structure by sea water, and significant differences between gel pores in concretes made with and without supplementary cementitious materials. A research program has been initiated to determine this knowledge including determinations of (i) pore closure (ii) water diffusion, & (iii) interaction of paste with sea water, all being monitored as a function of cure time.