The effect of damage on single and double hull construction to the ultimate strength of the ship

Abstract Ship construction typically includes single hull and double hull designs, each offering distinct advantages and disadvantages concerning the ship’s ultimate strength. Because a single hull does not have an inner hull or inner bottom, it may carry more cargo than a double hull. Compared to a single hull, a double hull offers greater safety during collisions and grounding incidents due to the presence of an additional inner hull and inner bottom. As a result, this influence has to be examined in relation to the ship design and construction specifications. This study aims to examine how damage impacts the ultimate strength of single and double hull ship designs when subjected to hogging and sagging conditions. Both single and double hulls’ midship cross sections are considered in the study. One side of the cross section is rotated by a force, while the other side is fixed under restrictions. In this case, just one side of the cross section is subject to the multiple point constraint. It is assumed that the midship cross section will remain flat during the gradual collapse process. The materials have uniform density, yield strength, Poisson’s ratio, and Young’s modulus, with single hull and double hull ships having identical proportions. An inner hull is incorporated into the simulation for the double hull structure. For simple analysis, longitudinal direction is done in a single frame space. This study employs an analytical method to assess the effects of damage on the structural integrity of single-hull and double-hull ships. The findings reveal that damage has a notable influence on the ultimate strength of both hull types. The moment-curvature relationship is utilized to represent the ultimate strength of these structures. Additionally, the paper illustrates the deformation patterns and stress distributions in single hull and double hull designs.