Non-stationary characteristic in nature wind has a great effect on buffeting performance of long-span bridges. The influence of key parameters in non-stationary wind velocity models on nonlinear buffeting responses of a super long-span suspension bridge was investigated in this paper. Firstly, four non-stationary wind velocity models are established by combing the time-varying average wind velocity with an exponential function and the fluctuating wind velocity with four modulation functions, respectively. These non-stationary wind velocity models have obvious non-stationary characteristics and then are validated by the classical power spectrum densities. Finally, three displacement responses of the bridge deck under four different independent variables of β in the exponential function and four modulation functions were compared, respectively. Results show that the turbulence intensities using two non-uniform modulation functions (NMF) are larger than those using uniform modulation functions (uMF). Moreover, the root mean square (RMS) values of three displacement responses increase with the decrease of β. Besides, the RMS values of three displacement under two NMFs are larger than those under two uMFs, and their RMS values under the second uMF are the smallest.

中文翻译：

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非平稳风速模型对闭箱梁悬索桥抖振性能的影响

自然风的非平稳特性对大跨桥梁的抖振性能影响很大。研究非平稳风速模型关键参数对超大跨度悬索桥非线性抖振响应的影响。首先，分别将时变平均风速与指数函数和脉动风速与四种调制函数相结合，建立了四种非平稳风速模型。这些非平稳风速模型具有明显的非平稳特征，并通过经典功率谱密度进行了验证。最后，分别比较了指数函数和四种调制函数中β的四个不同自变量下桥面的三种位移响应。结果表明，使用两个非均匀调制函数（NMF）的湍流强度大于使用均匀调制函数（uMF）的湍流强度。此外，三个位移响应的均方根（RMS）值随着β的减小而增大。此外，两个NMF下的三个位移的RMS值均大于两个uMF下的RMS值，且第二个uMF下的RMS值最小。