Multiple synchronized dynamic attenuators of wind-induced oscillations of Rio-Niteroi Bridge

摘要

A new system of multiple synchronized dynamic attenuators (MSDA) was recently installed in the Rio-Niteroi bridge to prevent that cross-winds of relatively low velocities set into vortex-induced oscillations the lightly damped and remarkably long three continuous spans of the steel twin-box-girder bridge. This deterrent aspect of the world's largest steel box-girder bridge and the conceptual design of this passive control system, together with its main geometric and physical characteristics, are briefly described herein. A short account is given on how an experimentally calibrated mathematical-numerical model for the aeroelastic problem, combined with optimization techniques, were used to assist in designing feasible mechanical and robust dynamic-control devices to upgrade the serviceability of this bridge and users' comfort. The performance of the MSDA system is demonstrated through experimental measurements and comparisons of numerical results obtained for time responses of the original and the controlled structure.