STRUCTURAL COUPLING EFFECTS OF COUPLED FLUTTER ON AKASHI STRAIT BRIDGE

Abstract

In the wind tunnel tests of Akashi Strait Bridge elastic full-scale model performed by Honshu-Shikoku Bridge Authority, damping-velocity characteristics of could not be explained by conventional 2DOF (vertical and torsional motion) flutter analysis and 3DOF (vertical, horizontal and torsional motion) flutter analysis could show better fitting to the tests results. However, there are some questions why 3DOF flutter analysis can better fitting to the results, even though the aerodynamic derivatives associated to horizontal motion is much smaller than the other derivatives. Therefore, in this study, the effects of horizontal motion and drag force are investigated by using 3DOF or multi-mode step-by-step analysis. In consequence, the coupled flutter of Akashi Strait Bridge can be characterized by aerodynamically 2DOF coupling and structural-coupling between horizontal and torsional motion.