A three-year project on Structural Health Monitoring of railway bridges: main results and lessons learnt

Bridges and viaducts worldwide are threatened by ageing, increasing loads and climate-related extreme events. The situation calls for immediate actions to prevent catastrophic failures and extend the life of our infrastructural heritage. In this regard, thanks to significant efforts from academics, Structural Health Monitoring is paving its way towards application in the real world. Unlike the simple monitoring activity, which is not new in the field, SHM is more identifiable as a paradigm, encompassing several steps and involving many stakeholders. Also, the focus is not on a project level but on the network as a whole. Such a new perspective offers the opportunity - and obliges at the same time - to look for synergies among different bridges, with the aim of designing standardized guidelines to foster SHM scalability. Embracing this vision, in 2020, the Mechanical Engineering Department of Politecnico di Milano gave birth to a project oriented to testing the application of Structural Health Monitoring on the Italian railway infrastructure. The project had a twofold objective: on the one hand, the realisation of an automated software to extract and deliver information from the monitoring systems installed on three pilot bridges; on the other hand, the draft of guidelines that could report the lessons learnt and generalise as much as possible the design and exploitation of SHM on railway bridges. Given the interest in the feasibility of an extensive adoption of such practice, the pilot bridges were selected to be representative of the whole network. This paper wraps up the three-year project, intending to share the experience gained in the field and the take-home messages for future applications of SHM, with a focus on the key aspects for a broad spectrum adoption of this paradigm.