In this paper, focusing on a fatigue crack occurring in a main girder of a continuous steel girder bridge, assessed is the remaining structural safety of the steel bridge with such a fatigue crack. In this study, an elastic-plastic finite displacement analysis was carried out for the steel three span continuous non-composite girder bridge with four main girders with an observed long fatigue crack of about 1.1m in the web plate of the main girder during a inspection. From the analytical result, it was found that the load re-distribution function of the multi main girders system was very effective and the remaining load carrying capacity of the target bridge was enough not to cause a sudden collapse of the entire bridge.
