索网结构振动模态特性分析

采用子空间迭代法，结合2个工程实例，对索网结构的自振特性进行了计算分析，研究了一般索网结构的频率分布特性以及钢索应力刚度、结构质量和矢跨比等结构参数对自振特性的影响．此外，还考虑了几何非线性对结构应力刚度的影响，考虑位形修正进行了模态分析．研究结果表明，索网结构振型密集，影响其自振特性的主要结构参数是索网的初始张力和索网屋面的分布质量．

Analysis of Modal Properties of Cable-Net Structures

The modal properties of two practical cable-net structures, as examples, were analyzed with the sub-space iteration method to investigate the characteristic of frequency distribution of general cable-net structures and the effects of structural parameters, such as steel cable stiffness, structure mass and rise to span ratio, on their free vibration properties. In addition, the modal analysis considering geometry update was carried out. The research results show that the vibration modes of a cable-net structure are close each other, the initial tensile force and the structure mass are two important factors influencing the free vibration properties of a cable-net structure.