Multimode Coupled Flutter and Buffeting Analysis of the Akashi-Kaikyo Bridge

Abstract

Flutter and buffeting are both issues of utmost concern in the wind-resistant design of long-span bridges. Multimode flutter and buffeting analysis of the Akashi-Kaikyo Bridge, which is the world's longest suspension bridge with a center span of 1,991 m, were performed, and the analytical results were compared with wind-tunnel test data obtained from an aeroelastic full model of the bridge. The multimode flutter analysis was in good agreement with the measurements and exhibited a significant coupling among modes. The multimode buffeting analysis also showed excellent agreement between the analysis and measurements in vertical and torsional response. However, for reasons likely associated with the assessment of lateral aerodynamic damping, the analysis overestimated lateral response. Significant coupling among modes was also observed in the buffeting analysis, and the multimode analysis predicted the measurement better than an alternate single-mode analysis method.