Structural safety assessment of continuous girder bridge with fatigue crack in web plate

This paper, which focuses on a fatigue crack found in a main girder of a continuous steel girder bridge, assesses the remaining structural safety of the steel bridge with such a fatigue crack in order to judge whether or not urgent action such as closure to traffic or necessary temporary repairs and strengthening should be carried out. Therefore, an elastic-plastic finite displacement analysis is carried out for the continuous three-span non-composite steel girder bridge with four main girders in which a fatigue crack about 1.1 m long in the web plate of the main girder was discovered during an inspection. From the analysis results it is found that the load redistribution function of the multiple main girder system was effective and the remaining load-carrying capacity of such a bridge system is such that there will be no sudden collapse of the entire bridge.