Dynamic Monitoring and Identification of a New Italian Cable-Stayed Bridge During Dynamic Load Tests

The new cable-stayed bridge built for the North-South axis road of Bari in order to overpass the railway of RFI and Ferrotramviaria s.p.a. has been recently built and opened to the traffic. The bridge is 626 m long and the central cable-stayed bays have a total length of 225 m. They are supported by 30 cables connected to a central upside down Y-shaped pylon. The peculiarity is that this column is about 60° rotated with respect to the axis of the bridge deck. Just a couple of weeks before its opening the last dynamic check has been designed and performed by the authors with the aim to identify the first frequencies and modes. 26 piezoelectric accelerometers have been utilized in different positions of the cables-stayed bays to record the accelerations produced by environmental forces and by the impact produced by a loaded truck of about 38 tons passing over a bump. Operational Modal Analysis has been applied by mean of Artemis software to determine the first fundamental frequencies, the mode shapes and damping factors.