Multimode coupled flutter and buffeting analysis of the Akashi-Kaikyo bridge

Flutter and buffeting are both issues of utmost concern in the wind-resista nt design of long-span bridges. Multimode flutter and buffeting analysis of the Akashi-Kaikyo Bridge, which is the world's longest suspension bridge w ith a center span of 1,991 m, were performed, and the analytical results we re compared with wind-tunnel test data obtained from an aeroelastic full mo del of the bridge. The multimode flutter analysis was in good agreement wit h the measurements and exhibited a significant coupling among modes. The mu ltimode buffeting analysis also showed excellent agreement between the anal ysis and measurements in vertical and torsional response. However, for reas ons likely associated with the assessment of lateral aerodynamic damping, t he analysis overestimated lateral response. Significant coupling among mode s was also observed in the buffeting analysis, and the multimode analysis p redicted the measurement better than an alternate single-mode analysis meth od.