Flutter Control by a Multiunit Gyroscopic Stabilizer: Deterministic-Stochastic Analysis of the Messina Strait Bridge Prototype Design

Long-span cable-supported bridges are increasingly vital structures. Their aerodynamic properties and deck flexibility make them susceptible to wind load effects, with flutter being a major concern as it can lead to structural failure. To address this issue, this paper utilizes a novel, multiunit gyroscopic device for flutter control. The stabilizer is installed in the interior of the deck cross section of the Messina Strait Bridge (1992 prototype design), the longest suspension bridge currently scheduled to be built. First, a mathematical model of the multiunit gyroscopic device was derived and employed to evaluate its effectiveness in altering the critical flutter wind speed. Second, structural reliability against flutter failure was evaluated accounting for random aeroelastic load perturbations, which are a primary source of uncertainty. Monte Carlo simulations were employed to predict the flutter limit-state probability, the reliability index and to investigate the stabilizer's efficiency within the practical operational range. To test the effectiveness of the proposed prototype in enhancing critical wind speed, a supplementary numerical study was conducted, varying the gyricity of the gyroscopic device. The numerical results indicate that the gyroscopic stabilizer is highly effective, with the bridge's flutter threshold increasing by more than fifty percent, depending on the gyricity of the gyroscopic device.