Abstract
Scallops are generally set on lateral gusset plates connected to webs of steel I-section girder bridges in order to avoid intersection of weld lines. The gussets are subjected to stresses by sectional forces in lateral bracing, sway bracing and cross beam in addition to main girder. Therefore, stress distribution is complex in the gusset scallop. In actual bridges, fatigue cracks were found at the boxing weld toe in the end of gussets and boxing weld toe at inner of scallops. In this study, FE analysis has been performed to make clear the stress behavior of lateral gusset plate. Then in comparison with the result of the normal fatigue design, and confirmed the structure improvement effect.
