Progress in the development of phenomenological models for engineering infrastructure applications

For the management of infrastructure over long periods of time and for the assessment of infrastructure that is already deteriorating, structural engineers need to be able to predict the likely future deterioration of their structures. Conventionally engineers rely heavily on mathematical models or their equivalent, since testing of major infrastructure is not feasible. They therefore also need mathematical models for likely corrosion - both for general corrosion and for maximum pit depth. The proposed presentation will outline the approach that has been used to date for modelling the corrosion of structural steels in marine environments. It also will outline current research to extend the work to coastal and inland exposure conditions. The modeling approach is based on corrosion science fundamentals, includes microbiological aspects and invokes probabilistic notions to account for the inevitable uncertainties attached to enumerating the environment and other conditions and in prediction. The approach taken for model development interprets data using an ‘a priori' model in the sense of Bayes inferential theory, rather than using data alone to dictate a ‘model', such as typically resulting from correlation studies. Some example results are given to illustrate this approach.