Since the main sections of the Chong Qi Bridge in China displayed a high dynamic response to wind induced vibrations,theoretical and experimental analysis have been performed to assess the resulting deflections for the lock-in case for vortex shedding and the resulting fatigue loading of the bridge deck.The results from a basic assessment according to Eurocode 2 [3],a detailed numerical analysis and wind ttmnel tests showed a good correlation and revealed that the structure would display oscillations of +/-150 mm for the determined inherent structural damping of D =0.3%.