Investigation and prevention of deck galloping oscillation with computational and experimental techniques

Although bridge aerodynamics usually involves such kinds of wind-induced responses as vortex shedding excitation, buffeting and flutter instability, a bluff cross section for even a short-span bridge, combined with a lightweight superstructure in reality, has brought its galloping-type instability as an important issue for bridge aerodynamics. This paper focuses its attention on the galloping-type oscillation taking as an example of the Yadagawa Bridge in Nagoya, Japan. The deck galloping oscillation of this continuous beam bridge has been thoroughly investigated by CFD computational estimation and wind-tunnel experimental confirmation using a sectional model and an aeroelastic model. Three aerodynamic preventive means, including the 40% slotted deck, the 80% slotted deck and the structure with aerodynamic deflectors, have been suggested and studied to improve the galloping characteristics of the bridge deck.