基于自由振动响应的基础隔震建筑减震能力评估方法研究  

Evaluation method of seismic isolation capability of base-isolated buildings based on free-vibration response

作　　者：周光鑫 魏明宇 熊峰 宋进 吕洋 ZHOU Guangxin;WEI Mingyu;XIONG Feng;SONG Jin;LU Yang(Sichuan Institute of Building Research,Chengdu,610081,China;Key Laboratory of Deep Underground Science and Engineering(Ministry of Education),School of Architecture and Environment,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川省建筑科学研究院有限公司,四川成都610081 [2]四川大学深地科学与工程教育部重点实验室,四川大学建筑与环境学院,四川成都610065

出　　处：《世界地震工程》2022年第1期119-126,共8页World Earthquake Engineering

基　　金：四川华西集团科技项目(HXKX2017101)。

摘　　要：目前国内外已修建完成了大量隔震建筑,但仅有少量经受了地震检验,绝大部分隔震结构减震能力能否达到设计目标尚存疑问。本文针对基础隔震建筑,提出了一种基于自由振动响应的减震能力评估方法。首先,对隔震建筑进行多级幅值初位移自由振动原位试验,获取结构的抗震能力曲线;其次,根据地震反应谱建立地震需求曲面,进而确定隔震结构性能点;最后,根据抗震设计规范计算水平减震系数,直接评估隔震结构的减震能力。与传统基于静力推覆的能力谱法相比,该方法考虑了动力效应,更接近实际情况;且性能点的确定过程无需迭代,操作简便。本文给出了上述评估方法的详细步骤,并以某实际工程为数值算例初步验证了评估方法的有效性。A large number of seismically isolated structures have been built around the world,but only few of them have been stricken by earthquakes.It remains an issue whether these structures could perform effectively to meet the prescribed design target.To this end,the paper presents a method for evaluating seismic isolation capacity of base-isolated buildings using free-vibration test results.The proposed method is based on snap-back tests using different initial displacements to obtain seismic capacity curves,enabling in-situ tests on real base-isolation systems.Seismic demand surface of the system is established using earthquake response spectra to determine a performance point.The code-compatible horizontal seismic response reduction factor is adopted todirectly evaluate the seismic isolation capability of the isolation system.Compared with the conventional static push-over based capacity method,the proposed approach takes into account dynamic effects,and it does not require iteration to determine the performance point.A detailed step-by-step procedure is provided for the evaluation method of which the effectiveness is demonstrated using a numerical example of a practical engineering project.

关 键 词：基础隔震建筑 减震能力 评估方法 自由振动响应 水平向减震系数 

分 类 号：P315.8[天文地球—地震学]