超高层结构不同周期地震动响应研究

摘要

以某高度为299.3 m的框架-核心筒结构为对象,研究了不同长短周期地震动对超高层结构动力响应的影响.以地震动周期为标准,选取了35条地震动,并对其进行了分类.使用所选地震动对结构进行了弹性及弹塑性时程分析,从内力、位移以及能量耗散的角度对比分析了超高层结构在不同长短周期地震动作用下的响应差异.结果表明,随着作用于超高层结构地震动周期的增长,结构动力响应、构件内力、加强层处核心筒剪力墙剪力和框架柱轴力突变显著增大,罕遇地震动作用下,结构能量耗散机制有所改变,且长周期地震动作用下,超高层结构动力响应远大于规范规定的普通地震动,结构偏于不安全.%A 299.3 m-high frame-core tube structure is studied here.The effects of super high-rise structure dynamic response under different periods of ground motion are investigated.Based on the ground motion period,35 ground motions are selected and classified.Elastic and elasto-plastic time-history analyses are carried out with the selected ground motions,based on the internal force,displacement and energy dissipation,the difference response of super high-rise structure under different periods of ground motion is analyzed.The results show that the dynamic response of the structure,the internal force of the member,the range of core shear wall shear force and frame column axial force changes significantly increased with the period of ground motion increases.The energy dissipation mechanism of the structure is changed under the rare ground motions.The dynamic response of super high-rise structure under the action of long period ground motion is much larger than the specification of ground motion,the structure is unsafe.