Aerodynamic interference and vortex-induced vibrations on parallel bridges: The Ewijk bridge during different stages of refurbishment

Abstract

This paper presents the results of sectional wind tunnel studies of the Ewijk bridge, a 270m span cable-stayed bridge crossing over the river Waal in Netherlands, which during its refurbishment was doubled with a close parallel bridge. The aerodynamics of parallel bridges may be complex and unpredictable, therefore specific wind tunnel tests were conducted.The tests were performed with sectional models in a 1:50 scale with the aim of identifying the aerodynamic interference effects between the two decks, in terms of aeroelastic stability, vortex-induced vibrations, and stationary aerodynamic loads. Several configurations were tested, since during various stages of refurbishment, the profile, the eigen-frequencies, the mass, and the relative position of the deck change.Results show that for the considered case, the interference effect is characterized by a significant change in the steady aerodynamic coefficients, vortex-induced vibrations of the upstream box-girder and forcing of the downstream bridge section, and no stability problems.