Fatigue Reliability Method with In-Service Inspections

摘要

The first order reliability method (FORM) has traditionally been applied toprobabilistic fatigue analyses for single inspection intervals. Accounting for inspections then requires several sequential FORM analyses and that the random distribution of crack lengths be recharacterized following each inspection. The augmented FORM presented here allows the reliability analyses to span several inspection periods without explicit characterization of the crack length distribution subsequent to each inspection. The method thereby preserves the attractive feature of FORM in that relatively few realizations in the random variable space need to be considered. Examples are given which show that the present methodology gives estimates which are in good agreement with the Monte Carlo simulations and is efficient even for complex components. (KAR) P. 3.