WELD REPAIR OF CRACKED BEAMS AND RESIDUAL FATIGUE LIFE

Abstract

Fatigue cracks often initiate at as-welded toe of various attachments where stress concentration is high. Bending fatigue tests were carried out on two beams with welded cover plates and gussets. About forty fatigue cracks were observed, when the cracked parts were successively repaired with stopholes and splice plates. The fatigue test results were compared with previous test data. The cracked beams were further repaired with groove welds and fatigue tests were continued. Fatigue cracks initiated and propagated from weld defects near the end of the attachments. Fatigue life of repaired parts was somewhat longer than that of as-welded one due to grinding the wel