Residual stresses are present in many civil structures due to manufacturing actions causing plastic deformations. Nevertheless, these stresses are not often taken into account when considering the design of these structures, especially when assessing fatigue problems. This remains true for orthotropic steel bridge decks. Due to their many complex welding details, these decks are sensitive to fatigue. To increase the understanding of the fatigue behavior of welded details, an improved analyzing tool using linear elastic fracture mechanics is proposed in this paper. Apart from the fatigue life of the weld detail, the crack propagation and crack growth direction are also evaluated with an XFEM model. Application of this method to the case of the orthotropic steel Temse Bridge in Belgium results in crack propagation very similar to reality. It also demonstrates that the fatigue calculations need to include residual stresses to comply with the real behavior of crack propagation.
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