Design and load-bearing failure analysis on the adhesive connection structure of composite ship deckhouse based on submodeling method

This paper aims to design a practical adhesive connection structure between the composite deckhouse and the steel main hull, and to evaluate the load-bearing property and failure behavior of local joints under the overall structural loads acting on the deckhouse.

Using the submodeling approach, the local joint region is coupled with the whole deckhouse model, and a parametric analysis is conducted on the adhesive layer through numerical simulations focused on the composite-to-steel slot connection scheme. Subsequently, the mechanical response characteristics of the connection area at the base of the deckhouse under splash loading conditions are evaluated, and a localized destructive test is conducted to investigate the failure modes of a real-size connection specimen.

The calculation results show that under splash-induced loading, the stresses in all parts of the adhesive connection structure remain below the ultimate material strength, maintaining a reasonable safety margin. When the load reaches approximately 3-fold the standard design load, initial damage mainly occurs at the corner of the stiffening beam skin. At around 10-fold the standard design load, the stiffening beam skin fails almost completely. Moreover, the damage features observed in the actual loading tests accord well with the results obtained from the refined local joint model.

This proposed slot adhesive connection structure is reliable and effective in meeting the strength requirements for the connection between the composite deckhouse and the steel main hull, and provides a useful reference for the engineering application of composite superstructures in the shipbuilding industry.