Fatigue Performance of Rib-to-Deck Joints in Orthotropic Steel Decks with Thickened Edge U-Ribs

Abstract

This study evaluated the fatigue performance of rib-to-deck welded joints in orthotropic steel decks (OSDs) with thickened edge U-ribs (TEUs). Fatigue performance of four rib-to-deck specimens with TEUs was investigated and compared with those of three rib-to-deck specimens with conventional U-ribs. Overall, the use of TEUs enhanced the fatigue strength of rib-to-deck joints. Finite-element modeling was conducted and validated by experimental data and sensitivity analyses. The validated finite-element model was then used to investigate the mechanism for the enhancement of fatigue strengths caused by use of TEUs and to evaluate the effects of weld penetration and open angle of rib-to-deck joints. Findings show that use of TEUs significantly improved the robustness of welded joints in terms of sensitivity to variations in the weld penetration. Appropriate increases in the open angle of rib-to-deck joints in OSDs with TEUs further improved fatigue performances. Finally, two full-scale orthotropic steel deck specimens were tested to further validate the effectiveness of TEUs.