Review of Non-Destructive Evaluation Techniques and Their Application to Inspection of Fatigue Cracks and Overstressing in Underwater Welded Steel Structures

A principal purpose of an inspection of off shore structures is to identify any structural flaws due to degradation or changes which would re quire remedial measures. Fatigue stresses and cracking in the area of welded tubular connections are a critical factor. This overview discusses the criteria for welding and initial crack size in terms of extended fatigue life, current underwater structural inspection requirements, and capabilities of available inspection techniques. Some current developments and trends in techniques for detection and analysis of fatigue cracks are discussed.