Assessment and management of existing bridges following the innovative Italian guidelines: A pilot study

In 2022, the Italian Government introduced innovative regulations for evaluating and monitoring existing bridges and viaducts, tackling issues related to risk classification, safety assessment, and monitoring. These regulations employ a multilevel approach for bridge inspections, safety assessments and monitoring procedures. The guidelines have garnered international acclaim for their forward-thinking approach. This paper proposes a comprehensive study concerning the whole process proposed in the new Italian guidelines, using a case study constituted by two prestressed RC box-girder half-joint span bridges that exhibited signs of ageing several years ago. The paper in deeply addresses all phases of the existing bridge safety assessment and management discussed in the guidelines from both a scientific and practical standpoint, in collaboration with the national agency for road administration. It starts from visual inspections, conducted for supporting the bridge safety assessments, and concludes with the experimental testing and structural monitoring of bridges. For the first time in the scientific literature, this work provides a pilot study for a proper and aware use of the innovative Italian guidelines, with focus on prestressed concrete bridges. The paper objective is to present advanced procedures for the classification, evaluation, and management of existing bridges to be adopted by road administrator, which may inspire international readers in upgrading codes of their own countries.