Gamma process model for time-dependent structural reliability analysis

The paper presents a stochastic gamma process model to account for both sampling and temporal variability associated with a deterioration process that increases risk of failure of an aging structure. The proposed method is more versatile than the random-variable deterioration rate model commonly used in the structural reliability literature. The reason being that the random rate model cannot capture temporal variability associated with evolution of degradation. The paper presents an intuitive interpretation and a comparison of assumptions associated with the random variable and gamma process deterioration models. Numerical results presented in the paper are expected to improve the general understanding of time-dependent reliability analysis for maintenance planning and optimization.