Influence of Nose Position of Edge Fairing on Aerodynamic Characteristics of Box Girder Bridge Deck

Edge fairing is often applied to box-girder bridge decks to improve their aerodynamic performance, particularly in long-span bridges. A thorough understanding of the aerodynamic response and flow behavior of bridge decks with edge fairings is essential for optimal design and ensuring wind-induced safety. This study presents a numerical investigation into the influence of the nose position of edge fairings on the aerodynamic behavior of box-girder bridge decks. Two-dimensional unsteady Reynolds-Averaged Navier-Stokes (URANS) simulations were performed using the k-ω-SST turbulence model, supported by appropriate validation studies. Both static and dynamic simulations were conducted for two configurations: edge fairings with nose-up and nose-down positions. The static analysis showed that the nose-down configuration offered superior aerodynamic performance compared to the nose-up configuration. In the nose-down position, the deck experienced reduced static wind forces with smaller fluctuations. Flow features such as leading-edge flow separation and reattachment, as well as trailing-edge flow separation, played critical roles in influencing aerodynamic forces. The dynamic simulations further revealed that the nose-down fairing configuration has improved aerodynamic damping in both torsional and heaving modes. In particular, leading-edge flow reattachment was identified as the primary contributor to enhanced aerodynamic damping in the nose-down configuration. Further, the relatively larger bottom plate slope had better aeroelastic responses in the nose-down position of the edge faring.