Uncertainty modeling in the fatigue reliability calculation of offshore structures

摘要

This paper presents a procedure of modeling uncertainties in the spectral fatigue analysis of offshore structures with reference to the reliability assessment. Uncertainties of the fatigue damage are generally embedded in response characteristics of the stress and the damage-model used. Besides commonly accepted uncertainties in offshore structural analysis, which are associated with the modeling of structures and the random wave environment, there are also uncertainties arising from joint flexibilities that occur during the response, the wave-current and water-structure interactions. Uncertainties in joint flexibilities are associated with degradation of member connectivities during a response process.