Scaling characteristics of the hull girder's ultimate strength subjected to the combined hogging moment and bottom lateral pressure: An empirically modified scaling criterion

Abstract

The ultimate strength of the ship hull girder under combined loads is closer to the load-carrying capacity during the actual sailing for considering the negative effect of the secondary load in some cases. Scaled models are designed to represent the prototype in ultimate strength experiments. To study the effect of the bottom lateral pressure on the scaled hull girder under combined loads thoroughly, a series of hull girders of a 10,000TEU container ship under different scale combinations of geometric length and plate thickness are analyzed. The relevant changes in the characteristics of ultimate strength and collapse behaviors caused by bottom lateral pressure are investigated. Results show that the ultimate hogging moment predicted by the traditional or the empirical scaling law proposed in the reference is significantly different from that obtained by numerical analysis when the scale ratio of the plate thickness is much smaller than the geometric scale ratio for ignoring the significant effect of the bottom lateral pressure. Correspondingly, an empirical scaling criterion is proposed to improve the accuracy of the converting process of the ultimate strength between scaled models and the full-scale prototype. Finally, the applicability of the proposed scaling criterion is verified by numerical results of a series of simplified hull girder models.