Research on infrastructures deterioration in the ReLUIS project: visual inspections and experimental tests

Diagnosing the deterioration of bridges is a priority in many countries, but the process is highly complex. This complexity arises from the wide variety of existing infrastructures, which have been constructed using different design methodologies, materials, and construction technologies, as well as from the influence of differing environmental conditions and maintenance activities. This paper presents the foundational principles and key results of the ReLUIS project, developed in Italy and funded by the Ministry of Infrastructure. The project aims to evaluate and enhance procedures for maintenance and monitoring of bridges. ReLUIS exemplifies a holistic approach to applied research, incorporating insights derived from real-world structures. Data from visual inspections of over 500 bridges have been analyzed, complemented by experimental and numerical studies on a wide variety of bridges. Herein a focus is proposed on prestressed concrete (PC) beams, halfjoint elements, in situ tests and structural health monitoring (SHM). The outcomes of this research provide recommendations for improving the assessment and monitoring of the infrastructure safety through a multiple level approach from initial visual inspections to detailed analyses of individual structures.