Probabilistic modeling of inspection results for offshore structures

Operators of marine structures have to ensure that structural integrity is maintained at a sufficient level during in-service life or in the case of the structure life prolongation. This can be achieved by Inspection, Maintenance and Repair plans (IMR), as rational aid-tools for decisional purposes. Such plans are complex and can be expensive. This leads to their global optimization, particularly regarding inspections. In this context, original results on inspections data in IMR plans are presented. The approach is based on decision and detection theories and include both the probability of false alarm and the probability of detection. It is shown how to introduce these probabilities in a decision scheme. The effect of false alarms and miss detections on the global cost of inspection planning is underlined through a basic example.