Breathing-induced Fatigue in Thin-walled Construction

The cumulative damage behaviour generated by web breathing was analysed, the process of the initiation and propagation of fatigue cracks induced thereby was studied, and their impact on the failure mechanism and the fatigue limit state of the girders was determined. It was found out that the above phenomenon led to a significant “erosion” of the beneficial post-buckled reserve of strength. Therefore, S-N curves were established for (i) the fatigue limit state and (ii) the onset-of-the-first-fatigue-crack limit state, specifying those periods after which checks for the appearance of fatigue cracks in bridge plate elements need to be carried out.