Modeling the dynamic corrosion process in chloride contaminated concrete structures

Corrosion of steel in concrete under service conditions is a process strongly influenced by the dynamics of environmental exposure. A total of 44 simulated bridge deck slabs were cast, and corrosion parameters were measured over a 5-year period. The monitored parameters included corrosion rate (linear polarization technique with and without a guard ring) and the concrete ohmic resistance and temperature. A series of 7 corrosion rates were established by admiring increasing amounts of sodium chloride. A non-linear regression model was developed, which demonstrates that corrosion of steel in concrete in service exposure conditions is a function of the concrete chloride content, temperature and ohmic resistance, and active corrosion time. Corrosion weight loss measurements demonstrated that the average annual corrosion rate is better estimated by the unguarded linear polarization method rather than the guarded ring method. (C) 1998 Elsevier Science Ltd.