COMPARISON OF REPAIR METHODS FOR FATIGUE CRACK INITIATED AT WELDED TOE BETWEEN STEEL DECK PLATE AND VERTICAL STIFFENER

Abstract

 Many fatigue cracks are observed at welded toe between steel deck plate and vertical stiffener. In this study, to compare the effects of fatigue life extension of three repair methods for crack initiated at the welded toe, bending fatigue tests were carried out. The repair methods are crack removal method by disk grinder, ICR treatment and stop hole. As the results of fatigue tests, it was clear that crack removal method by disk grinder and ICR treatment could prevent crack re-initiation. On the other hand, in case of stop hole, fatigue crack was re-initiated at stop-hole edge under low stress range, if stop-hole edge was not treated by disk grinder. Furthermore, the effect of fatigue life extension by the repair methods cold be evaluated qualitatively by FE analysis.