Dynamic ultimate strength of a ultra-large container ship subjected to realistic loading scenarios

When technically specifying ships for the future, the following aspects are examples of what we will have even more focus on than today: bigger, lighter, and faster. Thereby, the hydroelastic type of structural response will be more and more significant. Furthermore, it is well-known that the whipping-induced stresses are having a higher frequency than the ordinary wave-induced stresses; hence, some doubts are cast on the probability that the dynamic effects may provide additional strength reserves. Therefore, this research aims to analyze the dynamic ultimate capacity of ultra-large container ships under realistic loading scenarios. The hull-girder is subjected to a combined bending moment, resulting from a long-term hydroelastic analysis, with the lateral loads and to local loads given by different cargo loading cases. The numerical results are discussed, and the dynamic load factors are derived as the ratio between the dynamic capacity and the quasi-static one. Finally, it is shown that the strain rate effect is negligible in the analysis of the ultimate strength of ship structures subjected to whipping-induced stresses.