Development of innovative methodologies for the management, control and monitoring of existing infrastructures

Maintenance and monitoring of bridges are of paramount importance, not only from a structural engineering standpoint, but also in light of the significant social and economic consequences that may arise from malfunction or failure. Given the breadth of this topic and the evolving regulatory framework, this dissertation focuses on two critical aspects of the inspection process: visual inspections and special inspections for bridges that simultaneously feature post-tensioned cables and Gerber saddles. Visual inspections serve as the foundational step in any bridge assessment process. Their correct execution is essential to ensure reliable evaluation of structural conditions. In this work, we present the activities carried out by our research group in collaboration with the Fabre Consortium, including a statistical correlation model linking the observed damage level with the service life of the structures, based on a dataset of inspected bridges. A significant contribution of this thesis is the integration of innovative tools and methodologies to enhance inspection accuracy and efficiency. Specifically, we evaluate the use of drones, hyperspectral and multispectral imaging, and artificial intelligence techniques to support and potentially automate portions of the visual inspection process. The second part of the thesis addresses the growing regulatory demand for special inspections on critical structural components, such as post-tensioned tendons and Gerber saddles. To this end, a standardized inspection protocol is proposed, grounded in existing technical guidelines. This includes in situ stress-release measurements performed on tendons using X-ray diffraction equipment, previously validated through a laboratory-scale experimental campaign. Finally, the thesis outlines a streamlined BIM-based digitalization procedure for organizing and managing the collected inspection data, aiming to improve traceability, accessibility, and lifecycle management of bridge maintenance records.