Intelligent Planning Reliability-Based Inspections of Fatigued Structures for the Crack Initiation Period in the Weibull Case under Parametric Uncertainty

Abstract

In this paper, periodic inspections of fatigued structures, which are common practice in order to maintain their reliability above a desired minimum level, are based on the conditional reliability of the structure. It is assumed that only the functional form of the underlying distribution of time to crack initiation (when a technically detectable crack is present) is specified, but some or all of its parameters are unspecified. The new technique of intelligent planning is proposed in this paper to construct more accurate reliability-based and cost-effective inspections of fatigued structures with decreasing intervals (as alternative to constant intervals) for the crack initiation period in the Weibull case under parametric uncertainty. The technique is conceptually simple and easy to use. To illustrate the suggested technique some numerical examples are given.