OMA Applied to a Reinforced Concrete Railway Bridge Through a Reduced Measurement Set-Up

Structural Health Monitoring (SHM) is becoming a key tool to address the challenges posed by the maintenance of bridges and viaduc- ts. Modal parameters associated with the monitored structures, according to literature serve as well-known indicators of the health status, reflecting the physical and mechanical properties of bridges and their supports. Operational Modal Analysis (OMA) is a popular technique for identifying these modal parameters. An automated OMA procedure allows for tracking the evolution of modal parameters over time, providing a concise overview of the structure condition. This paper presents the results of an automated OMA procedure applied to a reinforced concrete railway bridge in service along the Italian railway line, using an SSI-COV based algorithm. The procedure is performed with a minimal setup of velocimeters permanently installed on the structure, exploiting a 3D finite element model tuned with preliminary tests to integrate experimentally unattainable information.