Structural condition assessment of long-span suspension bridges using long-term monitoring data

This paper focuses on developing an on-line structural condition assessment technique using the long-term monitoring data measured by structural health monitoring system. The seasonal correlation analyses of frequency-temperature and beam-end displacement-temperature for Runyang Suspension Bridge are firstly performed, respectively. Then the statistical modeling technique using a 6-order polynomial is further applied to formulate the correlations of frequency-temperature and displacement-temperature, on the basis of which the abnormal changes of measured frequencies and displacements are detected using the mean value control chart. According to the above analyses, it is found that modal frequencies of higher vibration modes and displacements have remarkable seasonal correlations with the environmental temperature and the proposed method exhibit good capability for detecting the micro damage-induced changes of modal frequencies and displacements.