Dynamic identification and vibration serviceability assessment of a wooden cable-stayed footbridge

This paper discusses the dynamic characterization of a 3 spans wooden cable-stayed footbridge newly built in Italy. The footbridge is 235 m long and consists of a 2-girder wooden deck. The edge spans are simply supported, while the mid one (about 150 m long) is sustained by 16 stays linked to 2 pillars. Ambient vibration tests and operational modal analyses are performed to identify the global dynamic behaviour of the structure and 17 stable vibration modes are identified in the frequency range 0-6 Hz. Moreover, the vibration serviceability is assessed performing in situ pedestrian load tests following the load protocols provided by Hivoss and Setra technical guidelines, and verifying the recorded accelerations with the maximum ones suggested by codes (fib bulletin 32 and EN1990:2002).