Bridge visual inspections: Experience of local authorities and the case study of the Corso Grosseto viaduct

Visual inspections are traditional method to collect information about bridge condition state. They are performed by qualified inspectors, during the bridge service life, which formulate judgments based on direct observation of the structure. This activity is however influenced by the subjectivity of expert opinions. Moreover, the frequency and the accuracy of bridge inspections may influence future maintenance activities. BRIDGE|50 is a research project aimed at investigating the residual structural performance of a 50-year-old bridge recently dismounted in Italy. The objectives include the validation, both in qualitative and quantitative terms, of national and international bridge inspection procedures through the comparison of the outcomes of visual inspections with the results of experimental tests. The paper describes bridge inspection procedures of local authorities, including Municipality of Turin, Metropolitan City of Turin, and Piedmont Region, and summarizes the visual inspections performed in the BRIDGE|50 research project before the bridge dismounting.