A Framework for Reliability-Based Fatigue Safety Factors for Flexible Risers

In the present paper, a procedure for reliability analysis of wave-induced fatigue in the tensile and pressure armours of flexible risers is described. The procedure is based on performing a number of parametric studies with respect to variables that influence the fatigue lifetime. The results of these parametric studies are subsequently combined with models describing the statistical scatter of the same parameters. By application of this procedure, the safety factors which are required in order to reach specific target reliability levels can be computed. Different SN-curves which correspond to different corrosive environments are considered.