远场长周期地震动作用下超高层建筑结构模态识别  

Modal identification of super high-rise structures under far-field long-period ground motions

作　　者：罗渊 杨江[1,2,3] 范涛 LUO Yuan;YANG Jiang;FAN Tao(Institute of Seismology,CEA,Wuhan 430071,Hubei,China;Wuhan Institute of Seismic Scientific Instruments Co.,Ltd.,Wuhan 430071,Hubei,China;Engineering Technology Research Center for Earthquake Monitoring and Early Warning Disposal of Major Projects in Hubei Province,Xianning 437000,Hubei,China)

机构地区：[1]中国地震局地震研究所,湖北武汉430071 [2]武汉地震科学仪器研究院有限公司,湖北武汉430071 [3]湖北省重大工程地震监测与预警处置工程技术研究中心,湖北咸宁437000

出　　处：《地震工程学报》2024年第5期1160-1171,共12页China Earthquake Engineering Journal

基　　金：中国地震局地震研究所和应急管理部国家自然灾害防治研究院基本科研业务费专项资助项目(IS202216317);湖北省重点研发计划项目(2022BAD059);地震科技星火计划项目(XH23027YB)。

摘　　要：远场地震动长周期成分显著,与高层、超高层建筑基本周期相近,容易产生放大效应,给高层、超高层建筑结构带来严重震害。以2022年9月17日21时41分至次日17时39分发生在台湾省花莲县M6.5、M5.7、M6.9和M 5.4地震为例,利用Hilbert-Huang Transform(HHT)方法,初步分析距震中超1000 km的武汉某超高层建筑结构台阵对这4次地震的结构动力响应观测数据,在对不同时间尺度的本征模态函数分量进行地震动长周期特性分析的基础上,重构各结构层的地震动,通过功率谱法得到结构层相对地面层的频率响应函数,并利用复模态指数函数法获得结构第一阶模态频率和振型。对4次地震中该超高层建筑结构模态频率和振型的初步分析表明:在花莲长周期地震动作用下结构未受到损伤。这一认识将为远场长周期地震动影响下超高层建筑的震后安全性评价提供重要参考。This paper examines the impact of long-period components of far-field ground motion,which can resonate with the natural period of high-rises and super high-rises,potentially leading to significant earthquake damage.The study focuses on the M 6.5,M 5.7,M 6.9,and M 5.4 earthquakes that occurred in Hualien County,Taiwan,China,from 21:41 on September 17,2022,to 17:39 the following day.Using the Hilbert-Huang transform method,the paper preliminarily analyzes the structural dynamic response data of a super high-rise in Wuhan,located more than 1000 kilometers away from the epicenter.By analyzing the long-period characteristics of the intrinsic mode function components across different time scales,the ground motion of each structural layer was reconstructed.The power spectrum method was used to determine the frequency response function of each structural layer relative to the ground layer.The first modal frequency and vibration mode were identified using the complex-mode Exp-function method.The analysis results indicated that the modal frequencies and vibration modes of the super high-rise structure remained intact under the long-period ground motions from the four earthquakes.This finding provides a crucial reference for post-earthquake safety evaluations of super high-rises in Wuhan when exposed to long-period ground motions.

关 键 词：远场长周期地震动 HHT方法 结构地震响应时程重构 模态频率 模态识别 

分 类 号：TU311.3[建筑科学—结构工程]