Abstract
The construction of lightweight structures poses new design challenges as a result of the different mechanics of deformation experienced by thinner-plated structures. Because of a reduced bending stiffness, thin plates are particularly sensitive to welding-induced distortions, which include a curvature, in addition to the axial and global angular misalignment observed on thick plates. The curvature shape and amplitude determine a local angular misalignment at the welded joint, which causes non-negligible secondary bending effects. Therefore, the commonly used stress magnification factors km solution for flat plates need a further development to include the curvature effect. This study proposes new analytical formulations, which extend the applicability of the existing solutions to the assessment of the structural stress of a curved thin plate under an axial load. The improved formulations are consistent with the geometrical non-linear finite element analysis under compression (up to sim 80% of the buckling limit) and tension (up to the yield strength). A sensitivity analysis is presented in order to show the dominant role of the curvature effect in the estimation of the km factor. Regardless of the load applied, the presence of the curvature causes a flat plate solution inaccuracy greater than 10% when the local angular misalignment is more than 1.25 times higher than the global angular misalignment in the case of a thin and slender structure.
Highlights
Prompted by energy efficiency and fuel economy reasons, the structural lightweight design for large-size structures has been in the spotlight of the recent research in several industrial fields
The results show that the influence of the boundary conditions (BCs) on the slender beam under tension is only visible for very low load levels
The structure took into account a geometrical non-linearity, and it was limited to small strains and moderate rotations, i.e. the von Karman assumption was utilised
Summary
Prompted by energy efficiency and fuel economy reasons, the structural lightweight design for large-size structures has been in the spotlight of the recent research in several industrial fields. Modern cruise ships have been designed to accommodate an increased number of cabins and open spaces, directing shipbuilding towards new solutions in terms of space and weight in order to increase the performance of the structure [1,2,3,4,5]. The implication of thinner structures poses new design challenges in terms of structural. The fatigue strength assessment of large structures such as ships is carried out by using the structural stress approach; see, e.g. The stress increase resulting from welding-induced distortions is considered separately in the computation of the stress magnification factor km. Different fatigue design codes and recommendations such as the IIW fatigue recommendations [9] classify the welding-induced imperfections as axial e and angular α misalignment.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
