ABSTRACT

Several fatigue life extension methods of a welded structure are coveted in the industry such as Tungsten-Inert-Gas dressing (TIG dressing). In this paper, experimental results from literature studies of pre-fatigued welded steel structures treated by TIG dressing were analyzed and showed that TIG dressing efficiency is dependent on the depth of the crack before treatment and the treatment penetration depth (aTIG ). A recommendation on the extended fatigue life involves the initial crack size (before treatment) as well as the remaining crack after treatment is provided. Based on this study, the improved fatigue life is found to be at least the as-welded fatigue life when the cracks have completely re-melted (recalibrated). A significant dependency of extended fatigue life on the remaining crack depth after treatment has been found.