单层平面索网幕墙结构的风振响应特性分析

建筑幕墙单层平面索网结构属于风敏感结构,目前对该类结构风振响应的相关研究很少,有必要深入开展其抗风性能的研究。以索网在平均风荷载作用下到达的新平衡位置为基准,采用频域法对其风振响应特性进行研究,主要分析了组合振型的选择、模态间的耦合效应等问题对索网结构风振响应的影响。分析结果表明,对单层索网结构进行风振响应分析宜考虑模态间的耦合效应;索网的第一阶模态在所有模态中占较大比重;对索网结构起主要贡献的振型集中分布在低阶模态区域内;采用部分低阶振型组合计算索网的响应与时域结果吻合较好,能满足工程精度要求。

RESEARCH ON WIND-INDUCED RESPONSE BEHAVIOR OF MONOLAYER CABLE NET FOR GLASS FACADES

Monolayer cable net system is sensitive to wind loads. There exist few researches on its wind-induced vibration performance,therefore it appears imperative to investigate the wind-resistant behavior of the cable net. The wind-induced response of monolayer cable net subjected to fluctuating wind loads is studied by frequency-domain method using the balance position when the cable net is subjected to mean wind pressures as the basis. Some parameters crucial to the responses of wind vibration are highlighted,including the number of contributing modes and the coupling effects between modes. It is shown that the modes contributing to wind responses lie mainly in a narrow range of low orders,of which the first mode is the most important. The results by some lower modes considering coupling in frequency domain agree with corresponding results in dynamic time-history domain,which satisfies the precision for practical application.