Buffeting of Tsing Ma Suspension Bridge: Analysis and comparison

A formulation for fully coupled buffeting analysis of long span cable-supported bridges is introduced first, which is featured mainly by a complete finite element approach and a pseudo-excitation method. The formulation is then applied to the Tsing Ma suspension Bridge in Hong Kong to examine effects of multimodes and intermodes of vibration on deck response, and to investigate buffeting response of the whole bridge with aerodynamic forces on not only bridge deck but also bridge towers and main cables. Finally, the computed buffeting responses of the bridge are compared with the key buffeting responses measured from wind tunnel tests. The results show that the effects from multimode responses are larger than single-mode responses in the vertical and torsional motions of the deck. The significant intermode responses may exist between the vibration modes of similar mode shapes or similar modal components. The buffeting of towers and main cables does affect the lateral vibration of bridge deck. The comparison between the computed and measured buffeting responses is satisfactory in general.