Fartygskonstruktioner AB wanted to investigate an alternative design bulkhead, presented by DNV, to their reference design of the corrugated bulkheads in their oil cargo tanks. The purpose was to lower the stress in the deck, the deck longitudinals, and the corrugated bulkheads. This was achieved by identification of problems, creation of calculation models and finite element analysis of the stresses. A subject and theory research strengthened the validation of the upcoming work.

A study was done to identify the problems. This included research of the subject and the theory behind it. With this knowledge, an analysis of the reference design was performed. A modified midship model was created based on the reference design model, which became the alternative design model. This was done in the program GeniE. When the alternative design was created, a submodel with a finer mesh was modeled. Even a modified submodelwas modeled. Properties were added to the models, and analysis in the software Xtract took place.

The results showed different stress levels in the four models, and focus was aimed at the deck, the deck longitudinals, and the corrugated bulkheads. The reference design presented the stress value in the current ship model, and the alternative design showed the stress levels in the alternative design. In the submodel, the results were focused on the interface between the deck and the corrugated bulkheads. The same was done for the modified submodel.

The first two analyses of the reference model and the alternative design model seemed to have a too coarse mesh to give reliable results. However, they gave a good reference value to investigate further with the submodels. In the submodel, the mesh was finer, and the results reflected values closer to reality. The modified submodel had the same mesh as the earlier submodel, and an added transverse girder decreased the stress level around the attachment between the deck and the corrugated bulkheads.

The conclusion showed that the submodel with the alternative design bulkhead had stresses above the permissible value. The modified submodel with the transverse girder reduced these stresses to within the maximum permissible value.