环境激励下基础隔震结构时变模态频率的温度效应  

Temperature effect of time-varying modal frequency of base-isolated structure under ambient excitation

作　　者：郑文智 王浩[1] 杜永峰[2] 茅建校[1] 

机构地区：[1]东南大学混凝土及预应力混凝土结构教育部重点实验室,南京210096 [2]兰州理工大学防震减灾研究所,兰州730050

出　　处：《东南大学学报（自然科学版）》2017年第5期999-1005,共7页Journal of Southeast University：Natural Science Edition

基　　金：国家重点基础研究发展计划(973计划)青年科学家专题资助项目(2015CB060000);国家自然科学基金资助项目(51578151;51438002);中央高校基本科研业务费专项资金资助项目(2242015K42028)

摘　　要：基于实测隔震层温度和结构加速度响应数据,分析了环境温度对基础隔震结构模态频率的影响规律.首先,采用小波变换方法识别了基础隔震结构时变模态频率;然后,分别采用单自由度简化模型和双自由度简化模型推导了环境温度对基础隔震结构模态频率的影响机理,对基础隔震结构模态频率与隔震层温度进行了相关性分析,提出温度对模态频率的影响系数,量化了隔震层温度对隔震结构模态频率的影响,并结合隔震支座温度相关性试验,对相关性分析结果进行了验证;最后,通过参数回归分析,提出模态频率与温度的相关性模型,并给出了温度对基础隔震结构模态频率的影响系数曲线.结果表明,实测温度影响系数曲线与隔震支座温度相关性试验结果表现出较好的一致性,可为基础隔震结构的性能评估提供可靠依据.Based on measured temperature and structural acceleration response of a base-isolated structure（ BIS）,the influence of the ambient temperature on the modal frequency of the BIS is analyzed. First,the wavelet transform method is used to identify the time-varying modal frequency of the BIS. Then,the influence mechanism of the ambient temperature on the modal frequency of the BIS is deduced by using the singular degree of freedom simplified model and the two degree of freedom simplified model,respectively. The correlation analysis between the modal frequency and the temperature of the BIS is investigated. The influence of the temperature on the modal frequency is quantitatively by the proposed influence coefficients. The correlation analysis results are verified by the temperature correlation test of isolation bearings. Finally,the correlation models of the modal frequency with the temperature are presented. The influence coefficient curves of the temperature on the modal frequency are obtained. The results showthat the measured influence coefficient curves agree well with the correlation test results,which can provide reliable basis for performance of BISs.

关 键 词：基础隔震结构 结构健康监测 小波变换 时变模态频率 温度效应 

分 类 号：TU352.12[建筑科学—结构工程]