Volume 23, Issue 4 (July 1995)
Microcracks: The Hazard Function and Reliability Inspection
Reliability inspections of structures for fatigue cracks are traditionally conducted at equispaced intervals because, it is assumed, the average slope of the hazard function following an inspection does not change from one inspection to the next. This study examines the common case where fatigue cracks nucleate continually over time. In such cases it is found that the slope of the hazard function after inspection may tend to increase from one inspection to the next, suggesting that inspection intervals should decrease with increasing service life. A formalism is introduced that allows calculation of the hazard function from microcrack data.