High definition video cameras for measuring movement of vibrating bridge structure

This paper presents the techniques and results of an innovative non-contact technique using low-cost high-definition video cameras and videogrammetric image processing techniques for measuring movement of vibrating object in daylight or night-time. Structural vibration can cause damage to engineering structure and reduces the lifespan of the structure, particularly highway bridges. The objective of the investigation was to determine the measurement quality of these video cameras for capturing the movement of structures during vibration such as the vibration caused by a trunk loading on a bridge. Indoor simulated object vibration was carried out to determine the suitable vibration levels for monitoring. An outdoor engineering bridge structure was also included in the investigation. High definition video cameras were utilised in the trials. The research findings show that these video cameras are suitable for low-accuracy close-up continuous monitoring of objects in low vibration level or at low frequency rate. The ground vibration around the camera setup site has minimal effect on the accuracy of the measurement. The current prototype developed has an achievable measurement accuracy of approximately ±0.17 mm in a three-dimensional reference frame.