Reliability of Structures Containing Short Cracks

Abstract

The reliability of structures containing short cracks is investigated. Short fatigue cracks are generally acknowledged to be small cracks propagating at rates that are faster or anomalous when compared to standard fracture analysis predictions developed for longer cracks. The extent of the short crack behavior tends to depend on mechanism such as the existence of notch plasticity surrounding the short crack. Techniques are presented for calculating the probability that short surface cracks will propagate without arresting to a size where the growth can then be analyzed using linear elastic fracture mechanics concepts. It is also shown how crack closure measurements can be incorporated into the fatigue reliability analysis to assist life predictions for short cracks.