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다국어 초록 (Multilingual Abstract)

The operational modal analysis (OMA) technique, which extracts the modal parameters of a structural system using ambient vibrations, has been actively developed as a field of structural health monitoring of cable-supported bridges. In this paper, the short and long-term modal parameters of a cable-stayed bridge were evaluated using the acceleration data obtained from the two ambient vibration tests (AVTs) and three years of continuous measurements. A total of 27 vertical modes and 1 lateral mode in the range 0.1 ~ 2.5 Hz were extracted from the high-resolution AVTs which were conducted in the 6th and 19th years after its completion. Existing OMA methods such as Peak-Picking (PP), Eigensystem Realization Algorithm with Data Correlation (ERADC), Frequency Domain Decomposition (FDD) and Time Domain Decomposition (TDD) were applied for modal parameters extraction, and it was confirmed that there was no significant difference between the applied methods. From the correlation analysis between long-term natural frequencies and environmental factors, it was confirmed that temperature change is the dominant factor influencing natural frequency fluctuations. It was revealed that the decreased natural frequencies of the bridge were not due to changes in structural performance and integrity, but to the environmental effects caused by the temperature difference between the two AVTs. In addition, when the TDD technique is applied, the accuracy of extracted mode shapes is improved by adding a proposed algorithm that normalizes the sequence so that the autocorrelations at zero lag equal 1.

참고문헌 (Reference)

1 김병화 ; 박민석 ; 이일근, "서해대교 사장교의 동특성 추출 : I. 모드형상" 대한토목학회 28 (28): 631-639, 2008

2 정대성 ; 김철영 ; 김남식 ; 윤자걸, "상시진동실험을 이용한 남해대교의 동특성 평가" 대한토목학회 22 (22): 1501-1514, 2002

3 홍동수 ; 김정태, "가속도 응답을 이용한 실물 콘크리트 거더 교량의 구조건전성 모니터링" 한국구조물진단유지관리공학회 14 (14): 165-174, 2010

4 Hernandez, W., "Water-Structure Interaction Analysis of a Segmental Bridge Using Ambient Vibration Testing at Different Water Levels, Proceedings of the 1st Conference of the European Association on Quality Control of Bridges and Structures" 200 : 1226-1233, 2022

5 Ding, Y. L., "Variability of Measured Modal Frequencies of a Suspension Bridge under Actual Environmental Effects, Proceedings of the 5th International Conference on Bridge Maintenance, Safety and Management" 1380-1387, 2010

6 Cho, S., "Structural Health Monitoring of a Cable-Stayed Bridge Using Wireless Smart Sensor Technology:Data Analysis" 6 (6): 461-480, 2010

7 Han, Q., "Structural Health Monitoring Research under Varying Temperature Condition : a Review" 11 : 149-173, 2021

8 Cunha, Á., "Recent Perspectives in Dynamic Testing and Monitoring of Bridges" 20 (20): 853-877, 2013

9 McDonald, S., "Operational Modal Analysis, Model Updating, and Seismic Analysis of a Cable-Stayed Bridge" The University of British Columbia 2016

10 Rainieri, C., "Operational Modal Analysis of Civil Engineering Structures" Springer 1-210, 2014