Wind tunnel test study on lattice high support of bridge in typhoon areaWind tunnel test study on lattice high support of bridge in typhoon area

Bridge grid support stability against typhoons is a key factor in ensuring the safety of bridge construction. This study employs wind tunnel force tests and Particle Image Velocimetry (PIV) experiments to investigate the typhoon stability of grid-type high supports. Based on wind tunnel force tests, the static force coefficients of grid-type high supports are measured under different flow conditions and wind angles. Utilizing PIV technology, a novel analysis is conducted on the flow field visualization of high-pier steel tube support models in horizontal and vertical plane flows. Quantitative analyses of the vortex core intensity and turbulence of single and double-pier supports are performed. The impact of wind direction on the aerodynamic characteristics of grid-type high supports is determined.The research indicates significant changes in drag, lift, and torque when calculating the wind resistance of grid-type high supports. Therefore, the influence of static wind loads in three directions needs to be fully considered in the calculations. Under a 45° wind deflection angle, vortex movement becomes more intense, reaching maximum vortex strength and turbulence intensity. This results in an increase in the average and fluctuating aerodynamic forces of the model. Compared to the four-legged grid-type high support model, the six-legged model exhibits relatively smaller vortex strength and turbulence intensity at the vortex core. Noticeable interference exists among the components of the grid-type high support, thus spatial three-dimensional characteristics should be considered in numerical simulations.By conducting wind tunnel experiments on grid-type high supports in typhoon-prone areas, the study ensures the safe use of these supports, enhances economic benefits, and broadens the application scope of grid-type high supports.