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Passive damping of vortex-induced oscillations of Rio-Niteroi Bridge

The remarkably long central spans of the Rio-Niteroi bridge are set into vortex-induced oscillations by cross winds of relatively low velocities. Whenever winds reach certain threshold speed ranges the response amplitudes grow large and the bridge is closed to traffic of any vehicle for the user's comfort and safety. This deterrent aspect of the world's largest span steel box girders bridge is explored to forward an explicit proposal for installing tuned vibration absorbers (TVAs) to attenuate oscillation amplitudes and, consequently, to improve bridge service life. A simple mathematical model, which yields response amplitudes that correlate favorably with wind-tunnel test results of a sectional model, is combined with optimization techniques to investigate and compare performances of both passive and active/passive feasible control devices. The obtained numerical results are then used to demonstrate that simple mechanical and robust TVAs come to be an advantageous intent to upgrade this bridge's serviceability.