환경 및 거동조건에 따른 쌍둥이 케이블교량의 동특성 분석

Abstract

With the development of structural health monitoring systems and operational mode analysis techniques, many studies have been carried out for condition assessment or damage identification of civil infrastructures based on dynamic characteristics such as natural frequencies, damping ratios, and mode shapes. However, the effect of environmental and operational conditions on the variability of dynamic characteristics results in a limitation for those vibration-based monitoring approaches. In this study, a predictive model based on multiple linear regression analysis was proposed to analyze the correlation between the dynamic characteristics of long-span bridges and environmental and operational conditions. First, the natural frequency and damping ratio of the target structure was estimated from the three-month measurement data by applying the automated output-only mode analysis algorithm. Then, the multiple linear regression analysis was performed to examine the relationship between dynamic characteristics and each environmental and operational variation. In addition, the prediction performance of the conducted multivariate regression model based on 80% of randomly extracted data was demonstrated by comparing the predicted values and actual estimates of the remaining 20% of the data. Finally, a stepwise regression analysis was employed to enhance the prediction performance of multivariate egression model.