Uncertainty analysis of ageing structures under a spatio-temporal degradation process

This study proposes a methodology for uncertainty analysis of structural capacity that accounts for the spatiotemporal deterioration process. The nonstationary and non-uniform behaviour of capacity degradation is modelled using a stochastic Gamma process combined with random field theory. The proposed framework integrates nonlinear finite element analysis with a surrogate modelling approach to enable accurate and efficient probabilistic assessment of ageing structural performance. The application problem investigated is the probabilistic assessment of the ultimate compressive strength of corroded plates, accounting for the variability in geometry, material properties, initial imperfections, and the corrosion process. The proposed methodology offers a more realistic assessment of the ultimate strength of ship plates compared to current state-of-the-art approaches.

Keywords: Uncertainty analysis, Stochastic process, Random field, Surrogate model, Corrosion..