FATIGUE STRENGTH OF VERTICAL STIFFENER JOINTS IN STEEL HIGHWAY BRIDGES

Abstract

Long-term fatigue behavior of plate girder specimens with four types of vertical stiffener connections is investigated through fatigue tests under constant amplitude and highway bridge variable amplitude loadings. Fatigue cracks are initiated from fillet weld toe at the top and bottom ends of each stiffener and from blow holes contained in the web-to-flange longitudinal weld. It is found that the fatigue failure life of all four connection details plotted against the maximum principal stress range satisfies JSSC fatigue category D.