Performance evaluation of monumental bridges: testing and monitoring “Ponte delle Torri” in Spoleto

This paper reports the main results of the experimental approach used for identifying the structural parameters and monitoring the dynamic response to the environmental loading of Ponte delle Torri (Towers Bridge) in Spoleto, Italy. In particular, the masonry wall drillings and laboratory tests on the cores obtained are described, together with the endoscopic survey and the flat-jack tests aimed to characterize the masonry mechanical characteristics. Then, the main focus is on the monitoring system, which is constituted of displacement transducers placed on the major cracks in the piers, seismic accelerometers placed on the bridge elevation next to the bridge deck, and a system of two ultrasonic anemometers which are used to record the wind speed fluctuations simultaneously with the bridge lateral accelerations. The results obtained give useful information to assess the actual state of the bridge and can be used for future decision making in planning maintenance strategies and restoration/consolidation campaigns.