Aerodynamic Investigation on a Long-Span Suspension Bridge with Central-Slotted Box Girder

In this paper, the authors discuss an aerodynamic investigation that included flutter and vortex-induced vibration performance of a long span suspension bridge with central-slotted box girder that was carried out based on the Xihoumen Bridge, the longest box girder suspension bridge in the world with a main span of 1650 meters. The flutter performance was investigated through sectional model wind tunnel tests and theoretical analysis. It was found that slot width has the most significant influence and that the variation of local aerodynamic configuration inside and outside the box girder section will also change the structural flutter performance in some comprehensive way. Central stabilizers can further improve the aerodynamic stability of the slotted box girder section. The “combined types” of stabilizers are recommended to improve aerodynamic stability to the bridge. Since heaving and torsional vortex-induced vibrations were observed when wind speed is relatively low, vibration control measure were investigated through wind tunnel tests.