A probabilistic physics-of-failure model for prognostic health management of structures subject to pitting and corrosion-fatigue

A combined probabilistic physics-of-failure-based model for pitting and corrosion-fatigue degradation mechanisms is proposed to estimate the reliability of structures and to perform prognosis and health management. A mechanistic superposition model for corrosion-fatigue mechanism was used as a benchmark model to propose the simple model. The proposed model describes the degradation of the structures as a function of physical and critical environmental stresses, such as amplitude and frequency of mechanical loads (for example caused by the internal piping pressure) and the concentration of corrosive chemical agents. The parameters of the proposed model are represented by the probability density functions and estimated through a Bayesian approach based on the data taken from the experiments performed as part of this research. For demonstrating applications, the proposed model provides prognostic information about the reliability of aging of structures and is helpful in developing inspection and replacement strategies.

► We model an inventory system under static–dynamic uncertainty strategy.
► The demand is stochastic and non-stationary.
► The optimal ordering policy is proven to be a base stock policy.
► A solution algorithm for finding an optimal solution is provided.
► Two heuristics developed produce high quality solutions and scale-up efficiently.