by Michael Jordan
Original: February 1999; Reprinted: May 2008
Since 1975, the development and use of structural maintenance programs have improved the reliability of heavily used container cranes. The programs, based on the principles of fracture mechanics and probabilistic methods, are designed to locate and detect fatigue cracks.
The booklet explains the fundamental principles of general yielding, fatigue crack growth, brittle fracture, the concepts of stress intensity and fracture toughness, fatigue design criteria, the statistical basis for fatigue criteria, and the selection of inspection intervals. The booklet also gives recommendations for what to do and what not to do when cracks are detected, describes typical crack patterns and good and bad fatigue details, and presents three specific examples of typical cracks and remedies based on actual occurrences.