Fracture mechanics as an improvement of fatigue life assessment in orthotropic bridge decks

摘要

Orthotropic bridge decks are widely used in long span steel bridges since they are extremelyrnlight weighted when compared with the load carrying capacity. In the past, fatigue life problems have sometimesrnbeen overlooked during design. Nowadays, approaches for fatigue design have reached their limits resulting inrnconservative design leading to overestimating the necessary dimensions. An improved fatigue life assessmentrnmethod is thus necessary. One possibility is to start using fracture mechanics. These techniques have manyrnadvantages since they form a more in-depth analysis. This implies that an entire crack propagation can bernevaluated. If the case study of the Temse bridge in Belgium is evaluated, a crack length of 461,703mm is foundrnwhile a crack length of 600mmwas detected in reality.Although the results showthe effort of fracture mechanics,rnimprovements are still necessary such as implementing residual stresses into the model.