Residual stresses can have a significant impact on the stability of structural members.
In the case of I-section beam elements, such stresses can impact lateral–torsional
buckling (LTB) capacity, particularly in the inelastic range. It is
possible for a built-up welded girder to have a lower LTB capacity than
that of a rolled one of identical cross-section. Concerns have been raised that such a
difference may render Canadian steel design standards unconservative for welded
girders. A paucity of residual stress data for current welded girders, however, prevents assessment of these assumed distributions.
In this study, residual stress measurements are carried out on a series of four reduced-scale
welded steel test girders. Testing consists of destructive sectioning tests and nondestructive ultrasonic measurements. A predictive residual stress model for modern welded girders is proposed, and the feasibility of the ultrasonic method for residual stress measurements addressed.