工程科学学报，第40卷，第3期：276-284,2018年3月 Chinese Journal of Engineering,Vol.40,No.3:276-284,March 2018 DOI:10.13374/j.issn2095-9389.2018.03.003:http://journals.ustb.edu.cn 桥梁模态频率与运营环境作用的相关性 周 毅”，孙利民》，谢漠文”，乔兰”回 1)北京科技大学土木与资源工程学院，北京1000832)同济大学土木工程防灾国家重点实验室，上海200092 ☒通信作者，E-mail:langiao@usth.cdu.cn 摘要桥梁模态频率随运营环境作用的变化规律是结构健康监测的研究主题之一.根据东海大桥6监测数据的周期变化 特性，识别了运营条件下主梁竖弯、侧弯、扭转基频变化的影响因素，采用偏相关系数和周期平均法对比了各因素的影响程 度.研究发现，东海大桥的模态频率存在1a、1周、1d、12.42h等变化周期，与结构温度、交通荷载、风荷载、海面高度等的变化 周期相吻合：结构温度和交通荷载是引起该桥频率变化的最主要因素，它们在各周期上的相对影响大小不同：周期平均法可 有效分离监测数据中的年、周、天周期成分，揭示不同运营环境作用与频率变化的相关性.研究结果有助于加深对桥梁运营期 频率变化的理解，从而更准确地评估结构性能. 关键词桥梁：模态频率：运营环境作用：相关性：结构健康监测 分类号TU311.3 Correlation of modal frequency variation for a bridge with operational and environmental actions ZHOU Yi,SUN Li-min2),XIE Mo-en,QIAO Lan) 1)School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China 2)State Key Laboratory for Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China Corresponding author,E-mail:langiao@ustb.edu.cn ABSTRACT In the vibration based structural health monitoring (VBSHM)field,the modal frequency of a structure is commonly used as an indicator for the global health condition of the structure.However,field measurements have shown that the modal frequency of a bridge varies with structural anomalies and the operational and environmental actions,e.g.,temperature and traffic loading.More- over,the latter variation usually exceeds the frequency shifts induced by the small and medium structural anomalies.To highlight the anomaly-induced frequency changes,the variability of modal frequencies of bridges with the operational and environmental actions must be investigated,and then,the action-induced frequency variations need to be eliminated.According to the periodic characteristics of the six-year monitoring data of the Donghai Bridge,this research identified the main actions that affected the modal frequencies of the first vertical/lateral bending modes and torsional mode of the girder of this bridge,and further,it compared the relative contributions of actions to the variability of frequencies through the partial correlation coefficients and the proposed cyclic averaging method.The results show that the modal frequencies of the Donghai Bridge vary at cycles as Ia,I week,Id,and 12.42h,which coincide with the inher- ent predominant cycles of structural temperature,traffic loading,wind loading,and sea levels,respectively.Structural temperature and traffic loading are the most influential factors for the frequency variation,and their relative importance is different for each individual cycle.The results also show that the cyclic averaging method can effectively separate the components in periods of I a,I week,and I d and can disclose the inherent correlation between actions and modal frequencies.This study helps in enhancing the understanding of the frequency variability for operational bridges and may lead to a more reliable evaluation of structural performance. 收稿日期：2017-09-13 基金项目：国家自然科学基金资助项目(51608034)：中国博士后科学基金资助项目(2016M600925):中央高校基本科研业务费专项资金资助 项目(FRF-TP-16O12A1)工程科学学报，第 40 卷，第 3 期: 276--284，2018 年 3 月 Chinese Journal of Engineering，Vol． 40，No． 3: 276--284，March 2018 DOI: 10． 13374 /j． issn2095--9389． 2018． 03． 003; http: / /journals． ustb． edu． cn 桥梁模态频率与运营环境作用的相关性 周 毅1) ，孙利民2) ，谢谟文1) ，乔 兰1)  1) 北京科技大学土木与资源工程学院，北京 100083 2) 同济大学土木工程防灾国家重点实验室，上海 200092 通信作者，E-mail: lanqiao@ ustb． edu． cn 摘 要 桥梁模态频率随运营环境作用的变化规律是结构健康监测的研究主题之一． 根据东海大桥 6 a 监测数据的周期变化 特性，识别了运营条件下主梁竖弯、侧弯、扭转基频变化的影响因素，采用偏相关系数和周期平均法对比了各因素的影响程 度． 研究发现，东海大桥的模态频率存在 1 a、1 周、1 d、12. 42 h 等变化周期，与结构温度、交通荷载、风荷载、海面高度等的变化 周期相吻合; 结构温度和交通荷载是引起该桥频率变化的最主要因素，它们在各周期上的相对影响大小不同; 周期平均法可 有效分离监测数据中的年、周、天周期成分，揭示不同运营环境作用与频率变化的相关性． 研究结果有助于加深对桥梁运营期 频率变化的理解，从而更准确地评估结构性能． 关键词 桥梁; 模态频率; 运营环境作用; 相关性; 结构健康监测 分类号 TU311. 3 收稿日期: 2017--09--13 基金项目: 国家自然科学基金资助项目( 51608034) ; 中国博士后科学基金资助项目( 2016M600925) ; 中央高校基本科研业务费专项资金资助 项目( FＲF--TP--16--012A1) Correlation of modal frequency variation for a bridge with operational and environmental actions ZHOU Yi1) ，SUN Li-min2) ，XIE Mo-wen1) ，QIAO Lan1)  1) School of Civil and Ｒesource Engineering，University of Science and Technology Beijing，Beijing 100083，China 2) State Key Laboratory for Disaster Ｒeduction in Civil Engineering，Tongji University，Shanghai 200092，China Corresponding author，E-mail: lanqiao@ ustb． edu． cn ABSTＲACT In the vibration based structural health monitoring ( VBSHM) field，the modal frequency of a structure is commonly used as an indicator for the global health condition of the structure． However，field measurements have shown that the modal frequency of a bridge varies with structural anomalies and the operational and environmental actions，e． g． ，temperature and traffic loading． More￾over，the latter variation usually exceeds the frequency shifts induced by the small and medium structural anomalies． To highlight the anomaly-induced frequency changes，the variability of modal frequencies of bridges with the operational and environmental actions must be investigated，and then，the action-induced frequency variations need to be eliminated． According to the periodic characteristics of the six-year monitoring data of the Donghai Bridge，this research identified the main actions that affected the modal frequencies of the first vertical /lateral bending modes and torsional mode of the girder of this bridge，and further，it compared the relative contributions of actions to the variability of frequencies through the partial correlation coefficients and the proposed cyclic averaging method． The results show that the modal frequencies of the Donghai Bridge vary at cycles as 1 a，1 week，1 d，and 12. 42 h，which coincide with the inher￾ent predominant cycles of structural temperature，traffic loading，wind loading，and sea levels，respectively． Structural temperature and traffic loading are the most influential factors for the frequency variation，and their relative importance is different for each individual cycle． The results also show that the cyclic averaging method can effectively separate the components in periods of 1 a，1 week，and 1 d and can disclose the inherent correlation between actions and modal frequencies． This study helps in enhancing the understanding of the frequency variability for operational bridges and may lead to a more reliable evaluation of structural performance．