Thermal field and residual stress of deck–rib double-sided welded joints in orthotropic steel decks

Double-sided welded deck–rib joints in orthotropic steel decks (OSDs) induce complex temperature fields and welding residual stresses (WRSs). In this study, a finite-element model of the joint is established, validated by way of the hole-drilling method, to compare double- and single-sided welding and evaluate the impacts of process parameters. Results reveal a unique thermal interaction in double-sided welding: a ‘preheating effect’ of the internal weld on the external weld, and a subsequent ‘reheating effect’ of the external weld on the internal weld. This interaction generates a unique double-peak temperature curve, rendering the WRS larger and more complex than in single-sided joints. To optimise manufacturing, limiting the welding speed ensures full penetration while reducing the maximum tensile lateral WRS at the external weld toe. In addition, shortening the welding interval decreases the maximum tensile lateral WRS, whereas an outside-in welding sequence increases lateral WRS and is not recommended.