Fatigue mechanical behavior of the repair techniques by grinding and wet welding

Abstract

Abstract This paper presents the results of a fatigue behavior study conducted on standard specimens obtained from a T-welded connection. The techniques of grinding and wet welding, commonly employed in the repair of offshore structures were utilized. The process involved a rectangular grinding in the weld area, followed by the application of wet welding to fill it. Two grinding depths, 6 and 10 mm, were investigated, and tests were performed at three immersion water depths: 50, 70, and 100 m. S-N curves were generated for air exposure conditions and the mentioned immersion depths. The results reveal a decrease in behavior in terms of stress and the number of cycles in the S-N curve as the immersion water depth increases. Particularly low-stress values were observed in connections with a 10 mm grinding depth at water depths of 50, 70, and 100 m. However, in the case of a 6 mm grinding depth and a 50-meter immersion depth, stress values were similar to those under air exposure conditions. This suggests that, in this specific configuration, the combination of grinding and wet welding could be effective in restoring the original service life of T-shaped connections. In contrast, in situations with a 6 mm grinding depth and immersion water depths of 70 and 100 m, significantly lower fatigue results were observed compared to air exposure conditions.