Techniques and instrumentation for structural diagnostics

This paper discusses principal aspects of condition monitoring for structural reliability. For specificity the paper focuses on the development of cracks. In the first part techniques and instrumentation for flaw detection are discussed. The topics include quantitative non-destructive evaluation, measurement models, laser based ultrasonics, neural networks; and integrated microsensors. The second part of the paper discusses the user of condition monitoring in the assessment of residual structural reliability. The topics in this part include probabilistic fatigue methods and fatigue reliability. The beneficial effect of inspections with a prescribed probability of detection on the probability of failure is demonstrated for the example of cyclic loading of a component containing an edge crack.