Aerodynamic Characteristics of a Cable-Stayed Bridge with a Span of 1,200m

The preliminary design of the cable-stayed bridge with a challenging main span of 1,200m is performed to connect Geoje Island and Masan City in the south-eastern part of Korea. The bridge site is exposed to the strong wind from typhoon every year. The design criteria require the bridge should resist the gust wind speed up to 73.5m/s at the deck level in service. Moreover, the stabilizing measures during construction should be considered such as temporary tied-down cables since the cable-stayed bridge erected by a free cantilever method is more vulnerable to wind loads under construction rather than in service. Thus 3-dimensional aeroelastic model tests considering erection stages are carried out to find the harmful wind-induced vibrations: vortex-shedding, buffeting, and flutter. Finally, the optimized stabilizing measures during construction are suggested.