Abstract:The long-span suspension bridges, which are notable flexibility, are sensitive to wind load. Using the finite element method, considering the geometric nonlinearity and displacement-load nonlinearity, the aerostatic stability of suspension bridges is studied when the non-uniform wind distributes symmetrically and asymmetrically along the main girder. The results show that the flow of positive angle of attack will reduce the critical stability wind speed of the bridges, the flow of negative angle of attack is conducive to the bridges to resist the instability of static wind. The impact of negative angle of attack on the static wind stability of the bridge is greater than that of positive angle of attack. When the flow is asymmetrically distributed, the critical stability wind speed can be determined by small wind angle of attack. When the flow is symmetrically distributed, the mean angle of attack can be selected to measure the aerostatic stability of the bridge. Incoming flow with non-uniform wind speed has an adverse effect on the aerostatic stability of the bridges. Moreover, the influence of symmetric distribution of non-uniform wind speed is greater than that of asymmetric distribution of non-uniform wind speed. Under varieties of initial angles of attack, the influence of non-uniform wind speed inflow on the aerostatic stability of the bridge is the same. That’s to say, the critical wind speed of aerostatic stability of the bridge decreases with the increase of the unevenness of the wind speed.