Abstract
Fatigue cracks were detected on welded joints between vertical stiffeners and orthotropic deck plate in 30 span of Hanshin Expressway bridges. This paper describes about study on retrofitting measures in weld of vertical stiffener cutting treating of the semicircle in orthotropic steel deck. At first, FEM analysis was conducted in order to evaluate the effect of stress reduction in this area by semicircle notching. Next, loading test using real size specimen was carried out. Finally, proposed retrofitting measures: semicircle notching was conducted on vertical stiffener of a bridge in the Hanshin Expressway and actual stress reduction effect was evaluated.