ABSTRACT
Orthotropic steel decks (OSDs) have several advantages: quick construction by pre-fabrication, reducing seismic load due to its lightweight, and so on. However, they have weak points: lower fatigue strength at deck to trough-rib welded joint and trough-rib to transverse-rib welded connections. Authors had already developed and verified an effective retrofitting method for deck to trough rib welded joint. Thus, a reinforcing method for the trough-rib to transverse-rib welded joins is needed. In this study, Angle steel retrofit is proposed as a retrofitting method for the joint, and it evaluated by FEA. At first, a finite element model of an actual OSD is created and it is validated and verified by using measured strain data of a field loading test. Then, the angle steel retrofit is modeled into the model and the effectiveness of the retrofit was evaluated by local stress change. As a result, peak stress at close to transverse-rib side weld toe (stress component of perpendicular to weld bead) could be reduced to about 1/3 of before, and stress at trough-rib side weld toe could be reduced to 1/3 of before. Therefore, the angle steel retrofit was effective to improve fatigue strength of the trough-rib to transverse-rib welded joint in OSDs.
