Probabilistic Models for Corrosion in Structural Reliability Assessment—Part 1: Empirical Models

Reliability theory for the assessment of existing structures for remaining safe life must consider the probabilistic deterioration of structural strength as well as multiple applied loadings. This requires good-quality models of deterioration processes. Models for corrosion, which have been applied in the literature for marine applications, are reviewed. It is shown that these usually are statistical only, using data pooled from many sources. They also use little or no theoretical insight. As a result, they provide poor-quality mean-value information and very high statistical uncertainties. The conclusion is that better modeling is required and that this involves much better understanding of the factors influencing marine corrosion. These factors are reviewed briefly, with particular emphasis on marine immersion corrosion of mild steel.