Abstract
A number of fatigue damages of different features have been reported on steel bridge girders of railway lines where EMUs are frequently operated. It has become important, therefore, to implement measures to extend the life of railway steel bridges and reduce maintenance work in the future. In this study, we clarified the fatigue strength of welded joints that have been used for welded steel railway bridges, predicted fatigue damages that would occur in the future, discussed measures to improve the fatigue strength by improving the weld toes and structures, and investigated the effect of such measures. We also studied the effect of high-speed operation in recent years in order to extend the life of railway steel bridges against fatigue.
