Design support tool for prediction of welding distortion in multiply-stiffened plate structures experimental and computational investigation

Many industries, such as shipbuilding, concerned with the fabrication of fusion-welded plate structures, face increasing challenges to produce lightweight structures. This design requirement is commonly met by using thin-plate, multiply stiffened, welded structures, but severe difficulties and high rectification costs are frequently incurred, related to the evolution of out-of-plane deformations. The overall scope of this study is to improve the applicability of computational prediction of distortion by providing simple and adaptable methodologies, which can be readily validated through experience of application in the industrial context. These methods are designed to be computationally economic and robust, and they are also generic with respect to material properties, welding processes, and thickness. The aim is to provide design engineers with the tools to explore alternative structural and process parameters and hence to find out if the outcomes will be acceptable, prior to embarking on manufacturing operations typical of large-scale welded structures. The validity of the simulations was investigated via full-scale tests where several fillet-welded 100 mm × 6 mm stiffeners were attached to 4 m × 1.5 m × 5 mm thick plates, according to different sequences. The computational models were used to optimize the welding scheme with respect to minimum out-of-plane deformation and welding sequence.