Fatigue damage and repair of steel railway bridges

A fatigue crack in the web plate developed at the toe of a fillet welded joint around the lower scalloped end of an intermediate stiffener is one of the typical fatigue damages of steel railway bridges. No fatal accident due to this kind of cracks has yet been reported, because these cracks grow very slowly and they have been discovered and repaired well before they grow to a serious extent by a well-organized inspection system. However, it is desirable to repair them effectively and economically, since there are many bridges employing the same kind of structural details. This report describes a field investigation and study to find the cause of crack initiation, an analysis of fatigue damage, and the establishment of an adequate repair practice.