基于虚拟激励法理论,推导了空间网格结构的抖振响应计算公式,公式中自动包含了激励之间的非完全相关性、振型之间耦合项的贡献。根据虚拟激励法直接求解出位移均方根的特点,推导了适用于多振型参振的脉动风等效静力荷载及相应的荷载风振系数计算公式。在此基础上,利用Matlab编制了相应的计算程序,并进行了算例验证与分析。算例分析验证了本文理论及程序的正确性,也表明本文方法具有很高的计算效率。本文工作为进一步系统研究大跨网格结构的风振随机响应打下了良好的基础。
On the basis of the pseudo excitation method (PEM), the formulas for the calculation of buffeting response for space lattice structures are derived. The partial correlation between wind excitations and the cross-correlation terms between the participant modes have all been involved automatically in the computations. Based on the fact that the PEM solves the root-mean-square displacements of the structure directly, the formulas for the equivalent static wind load and the corresponding wind fluttering factor in terms of loading are obtained, which are applicable to multiple participant modes. A computer program is then developed using the Matlab software, and two numerical examples are provided to verify the correctness of the theoretical derivations and the high efficiency of the program. This study forms sound basis for further systematic study on the wind-induced random vibration response for long-span lattice structures.