某超高层结构在长周期地震动下的结构响应分析

Seismic Response Analysis of A Super High-rise Structure under Long-period Ground Motion

已有震害研究表明,超高层建筑在长周期地震动作用下易出现'共振'现象,而目前国内规范对此的涉及较少,给结构安全带来一定的隐患。本文选取日本十胜冲地震和台湾集集地震中长周期分量明显的2条地震动记录以及2条普通地震动记录作为输入,以某拟建超高层结构为研究对象,运用Perform-3D软件进行了6度多遇和罕遇地震下的弹性和弹塑性时程分析,对比分析了结构在长周期地震动与普通地震动作用下的主要响应。结果表明,长周期地震动造成的结构响应如结构顶点位移峰值、层间位移角峰值等相比普通地震动更为显著,对于该超高层结构应该考虑长周期地震动带来的不利影响。

The existing seismic damage shows that the super high-rise buildings are prone to resonance under the long-period ground motion,but the Chinese Code are less involved,it may cause some problem to structural safety.In this paper two ground motion records with obvious long-period components from Tokachi-oki earthquake and Chi-chi earthquake and two ordinary ground motion records were selected as inputs.The proposed super high-rise structure was taken as the research object and Perform-3 D software was used to process the elastic and elastoplastic time-history analysis with the frequent and rare earthquakes input.The main responses of the structure under long-period ground motions and ordinary ground motions were extracted and compared.The results showed that the structural response caused by long-period ground motion such as the peak displacement of the structure and the maximun story drift are more significant than ordinary ground motion.For this structure,the adverse effects of long-period ground motion should be considered.