Inspection on the steel structures of bridge "Della Gerola" on Po river

The conservation of existing steel bridges in Italy, also after 100 or more years from their construction, represents currently an important topic of national relevance. In fact, many of these bridges require currently a repair intervention due to the degradation phenomena suffered over time. Moreover, most of them are included in the cultural heritage monuments because of their architectural or social relevance, such as the "Della Gerola" bridge. Built in 1916, it crosses the Po river along the provincial road n degrees 206 Voghera - Novara which connects the municipalities of Mezzana Bigli and Sannazzaro (to the north) with Cornale (to the south). It is a steel arch bridge, consisting of 8 arches for a total length of 756 meters. In order to support the maintenance activities, the bridge was subjected in 2019 to several inspections. This note presents the results of the inspection made to evaluate preliminarily the corrosion state of steel and to propose guidelines for repair.