A Practical and Cost-effective Expertise to Minimize Welding-induced Buckling Distortion in Thin-plated Panels for Commercial Shipbuilding

摘要

In response to welding fabrication of stiffened thin-plate panels, prevalent out-of-plane welding distortion inevitably takes place, and the welding-induced buckling is often the prime concern in the type of structures. In the study, the practical scheme to predict the onset of the welding-induced buckling instability was proposed. Plasticity-based elastic buckling prediction methodology was used for the prompt evaluation of the practical design modification aiming at the buckling prevention. The effects of the preventive measures, including local stiffening, control of welding heat input, and optimal welding sequences have been investigated through the numerical analyses. For the verification, mock-up panel block test were also carried out. The fillet weld size as the close proximity to the design requirement played a role to prevent local buckling in between stiffeners, but free edge buckling was unavoidable only by fillet welding control. Higher heat input for butt welding stages made the distortion worse, and eventually caused formidable inter-stiffener local buckling. Edge stiffening method was suggestible to prevent the distortion at the free edge of panel. As results, it has been suggested that the bucking distortion in thin-plated structures be hard to be prevented either only by changing structural design or applying low welding heat input, but instead a systematic expertise that is well customized to a relevant factory environment be established by utilizing resources available for the distortion prevention.