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.