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

The aerodynamic investigation including flutter and vortex-induced vibration performance of longspan suspension bridge with central-slotted box girder was carried out based on Xihoumen Bridge with the main span of 1650m, which will be the longest box girder suspension bridge in the world. The flutter performance was investigated through sectional model wind tunnel tests and theoretical analysis. It is found that slot width has the most significant influence, and 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 slotted box girder section, and the “combined types” of stabilizers are recommended. Since heaving and torsional vortex-induced vibrations were observed when wind speed is relatively low, vibration control measure was investigated through wind tunnel tests.