System Reliability of Ship Hull Structures Under Corrosion and Fatigue

摘要

System reliability of ship hull girder structures is evaluated considering uncertainties in ultimate bending capacity and sea loads. Lifetime structural deterioration models are developed at the system level. Time-variant random functions associated with corrosion and fatigue cracking are formulated to estimate the ultimate bending moment capacity. Still water and wave-induced bending moments are computed by using design-oriented and simplified direct methods. For sagging and hogging moments, structural performance in the intact hull condition is investigated considering different sea states as well as different ship operating speeds. The approach proposed is illustrated on a ship hull girder structure.