薄膜结构与风环境的耦合作用可分为静力耦合和动力耦合两类,静力耦合作用影响结构的基本动力特性,该影响可通过静力耦合参数,即附加质量与气动阻尼来度量。给出了获得附加质量与气动阻尼的实验方法,通过实验验证静力耦合作用的存在及其重要性,并探讨了这些参数的变化规律及其对薄膜结构自振特性的影响。试验结果表明,静力耦合作用与结构的振动模态有密切关系,一阶对称振型的振动耦合作用明显,附加质量最大可达结构质量的37%左右,气动阻尼可达到9%左右;静力耦合作用可显著降低结构自振基频,使结构振动频带宽度明显增加。
The interaction between structure and wind may be classified into static interaction and dynamic interaction. The static interaction, which can be evaluated by added mass and aerodynamic damping, influences the basic dynamic characteristics of structures. The method of obtaining added mass and aerodynamic damping is presented and the added mass and aerodynamic damping are measured through experiments. Variations of the interaction parameters and their influence on free-vibration characteristics are studied. The result indicates that the interaction is greatly influenced by the structural vibration modes, the symmetric vibration mode has a stronger interaction, the added mass can be about 37% of the structural mass, the aerodynamic damping can be around 9%, and the static interaction reduces the basic frequency of structural vibration and significantly broadens the spectrum band width.