Reliability and redundancy assessment of ships under different operational conditions

This paper proposes a framework for the assessment of structural safety of ships under different operational conditions by evaluating performance indicators such as reliability and redundancy. Flexural failure mode for several ship cross-sections is investigated. Reliability and redundancy are based upon the evaluation of the flexural capacities associated with the ultimate hull failure and the failure of the first stiffened panel within a selected cross-section. Furthermore, aging effects due to corrosion phenomena are investigated. Polar representations of reliability and redundancy are obtained for different encountered sea states, ship speeds and headings, covering a large spectrum of operational conditions. Load effects due to waves are computed based on strip theory, while flexural capacity is simulated using Latin Hypercube sampling. The proposed approach is applied to a Joint High Speed Sealift.