Aerodynamic Interference Effects between Parallel Bridge Decks

To meet the increasing demand for traffic capacity, new bridges are often constructed adjacent to existing ones, or multi-deck parallel bridges are built. Consequently, aerodynamic interference effects between adjacent decks become an important concern. This study focused on two under-construction multi-span parallel-deck bridges in China and conducted detailed wind tunnel tests to investigate the aerodynamic interference effects, including aerostatic coefficients, vortex-induced vibration, and flutter performance. The wind tunnel experiments also examined the influences of horizontal distances, vertical distances, and wind attack angles on the aerodynamic interference effects between adjacent decks. Furthermore, a fluid–structure interaction (FSI) numerical method applicable to twin parallel bridge decks was implemented in ANSYS Fluent, enabling the simultaneous capture of flow-field variations and surface pressure distributions during deck vibration. Based on the obtained flow fields and surface pressures, the mechanism of vortex-induced vibration under aerodynamic interference effects between twin-deck bridges was analyzed.