Buffeting Analysis And Wind-Induced Internal Force Of Long-Span Suspension Bridges

Suspension Bridge is a flexible architecture with strong geometric nonlinearity. The level of wind-induced response of suspension bridges will be significantly greater than the others under the action of the wind. It is more possible that the structure damage of excessive amplitude though the vibration is limited. Therefore, it is necessary to conducted on the analysis of buffeting response of long-span suspension bridges.In this paper, the fourth Nanjing Yangtze bridge (main span:1418m) was took as an example. Finite element software ANSYS was used to establish three-dimensional calculation model. The static and dynamic characteristics of the wind response were calculated separately. In addition, based on frequency domain analysis, software MATLAB was used to carry on the buffeting-response. The possible reasons for the discrepancies were analysized by compared the calculation results and the wind tunnel test results.The following five aspects were included in this paper:1.Section model wind tunnel tests were used to measure aerodynamic force coefficients and Flutter derivatives of girder section under different wind attack angle;2.With the change of static wind load, we get the displacement response and internal forces of the main girder and the bridge pylon by the finite element software ANSYS;3.Based on frequency domain analysis, software MATLAB was used to carry on the buffeting-response;4.The aerodynamic admittance function for the Sears and the calculation results for the 1 were compared, and the differences were described;5.Full-bridge aeroelastic model wind tunnel testing was took out to measure the buffeting displacement in turbulent wind field, and was compared with the numerical result, the differences were described as well.