Abstract: Cables, booms, and ties are important load-bearing elements of cable-bearing bridges. However, the traditional cable tension identification methods have the disadvantages of complicated operation, high cost, and low efficiency. This paper proposed a cable tension identification method for bridge structure based on Eulerian video magnification. The digital image of cable vibration collected by digital camera was processed by the phase-based Eulerian motion magnification, after which the image sequence after motion magnification was obtained. The edge image sequence was obtained by edge recognition algorithm based on Canny operator, and the displacement data of the mark point was extracted by edge positioning. Finally, the cable force was identified by frequency method. The applicability of the phase-based Eulerian motion magnification algorithm and the edge recognition algorithm based on Canny operator was discussed in the context of the arch bridge boom cable force test. Compared with the traditional acceleration sensor-based cable force testing method, the proposed cable tension identification method for bridge structure based on a motion magnification algorithm has the features of easy operation, low cost, and high efficiency. 

Key words:  , bridge engineering, cable tension identification, computer vision, eulerian video magnification, frequency method