Exploration of Next Generation Reinforced Concrete Corrosion Modeling with Interdependent Initiation and Propagation Stages

Most damage prediction models for reinforcing steel in concrete treat the corrosion initiation stage as being nearly independent from the propagation stage elsewhere in the system. A next generation chloride-induced corrosion interdependent model addresses those interactions by incorporating the corrosion prevention effect of the local potential drop caused by prior active-to-passive transitions in nearby steel portions. The effect of this Potential-Dependent-Threshold (PDT) approach was examined in a 3D realization, confirming and expanding conclusions from previous 1D and 2D models. Exploratory analysis was conducted for model result sensitivity to time step duration and activation zone size. It was found that the main outcome - a strongly lowered long term damage projection when PDT is taken into consideration - was reasonably robust to changes in those variables. The precise damage amount forecast was however sensitive to an extent that needs more detailed analysis. Sensitivity to time step choice appears to be resolvable in the limit, but selection of appropriate activation zone size needs addressing in future work.