LAUSR

Abstract Cruise ships have large and long superstructures, which are almost extending the whole ship length with discontinuous characteristics, such as side shell recess and many window openings. The superstructure effectiveness on hull girder longitudinal strength is a complicated but unavoidable issue in ship design stage. This paper has carried out a collapse experiment of steel model with superstructures, which is designed based on one actual cruise ship. Critical factors including initial imperfections and welding residual stress used in nonlinear FE analysis have been validated by the experiment results. Then, the superstructure effectiveness is analyzed to revise the increment-iterative to be applicable for ultimate strength evaluation for cruise ships. At last the combination action of bending moment and shear force is studied, and a new combination formula is proposed. The conclusions in this paper will be useful for ship design, rules amendment and safety assessment for cruise ships.