Variation of aerodynamic coefficients with air flow parameters on long span bridge deck

Abstract

Wind load is critical for bridges with high strength to weight ratio and determined experimentally using wind tunnel study that involves huge expenditure and time. In this study, behaviour of bridge deck is analysed by changing air flow parameters considering the structure submerged in turbulent flow using k-e turbulence model with boundary conditions calibrated to simulate neutral equilibrium atmospheric boundary layer. A computational model was considered to determine aerodynamic behaviour of bridge deck for different angle of attack of wind and results were compared with wind tunnel experiments keeping boundary conditions same. The aerodynamic behaviour of different bridge deck cross section are analysed using the computational model for different air flow parameters. The variation of aerodynamic coefficients are found and presented for box girder, plate girder, trapezoidal section and section of Great Belt East Bridge and attempt was made to select the optimum section to minimise the aerodynamic forces.