Modeling of fatigue failure mode in U‐rib to deck joints in orthotropic bridge structures

Various fatigue failure modes (i.e., cracking position and orientation with respect to a weld) can develop in welded rib to deck connections in orthotropic bridge deck structures. After demonstrating its effectiveness in correlating fatigue test data covering different failure modes, the master S‐N curve method was then adopted in this study for determining the critical failure mode in welded U‐rib to deck connections. These include considerations of additional failure modes potentially present in double‐sided welds between U‐rib and deck versus the traditional single‐sided weld design. The effects of weld penetrations and test loading conditions on failure mode development have been quantitatively established by means of the master S‐N curve method.