Numerical simulation of existing crack propagation of orthotropic steel bridge deck

Aim to improve the accuracy of crack propagation simulation, in this paper, an existing crack propagation numerical simulation method for the rib-to-deck welded joint which was vulnerable to fatigue in orthotropic steel bridge decks (OSDs) was established based on the theory of linear elastic fracture mechanics (LEFM). Firstly, the fatigue tests of typical structures of orthotropic steel bridge deck were designed and carried out. By applying a particular fatigue load sequence, beach marks were generated on the fracture surface of the specimen, which could be used to record the propagation process of existing cracks both in the depth and length direction. Then, based on the analysis of the fatigue test results and the metallographic observation of the fracture surface of the specimen, the real shape of the cracks, the propagation process of the existing cracks as well as the crack propagation parameters of the material were obtained. Finally, the crack propagation processes in the test were simulated and the fatigue life of the crack propagation was calculated. The results showed that the crack propagation simulation method adopted in this paper can effectively simulate the crack propagation path and predict the fatigue life of steel bridge deck, which can provide some reference for the maintenance of steel bridge deck.