Automatic Identification of Modal Parameters: Application to a Reinforced Concrete Arch Bridge

The paper presents the results of the experimental modal analysis of a reinforced concrete arch bridge, about 70 m long, crossing the Tiber river close to the city of Umbertide in central Italy. The dynamic tests were performed in operational conditions in February 2012 and represented the first known experimental survey carried out on the global dynamic characteristics of the bridge since its completion which approximately dates back to the early 50’s. Baseline modal parameters of the structure were extracted through an automated procedure recently proposed by the authors. Eight sufficiently long consecutive data sets were considered for this purpose and variations of modal parameters estimates among the different data sets were investigated.