ABSTRACT
The fatigue issue on orthotropic steel decks (OSDs) is closely related to the mechanical property of pavements. On the other hand, the fatigue cracks on OSDs can lead to local deteriorations of the supporting conditions of pavements, and therefore accelerates the fatigue damage evolution. This paper attempts to investigate the mutual effects on the OSD-Pavement system with existing cracks. Firstly, the finite element model of the OSD with penetrating cracks on the rib-to-deck welded joint is established. By obtaining the stress intensity factors along the crack front, the fatigue crack growth behavior is analyzed. The fatigue damage evolution on pavement is then studied using a continuum damage model in terms of the first principal strain range. According to the results, it can be addressed that the mechanical performance of pavements may help to resist growth of penetrating cracks on rib-to-deck welded joints on OSDs. On the other hand, the cracks will accelerate the fatigue damage on pavements as well. For a crack that reaches 0.75t (t as the deck plate thickness), the damage initiation on the pavement can be accelerated by about 16%. The results can be helpful in the decision making for the pavement maintenance of bridge, as well as the retrofitting works on OSDs, which may further benefit the life-cycle performance of the bridge.
