PSI - Issue 84

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ScienceDirect

Procedia Structural Integrity 84 (2026) 560–568

© 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Conference review under responsibility of the scientific committee of the Conference Keywords: Environmental effects; Multi-span bridge; Operational Modal Analysis; Structural Health Monitoring. 1. Introduction Continuous dynamic monitoring using operational modal analysis (OMA, see e.g. Magalhães & Cunha 2011) is a well-known non-destructive methodology aimed at extracting structural information from the response under ambient and/or operational excitations such as micro-tremors, wind and traffic. The raising scientific and practical interest on dynamic monitoring has many motivations, such as: (a) the ageing of existing structures and infrastructures; (b) the increasing complexity of new constructions (where the implementation of monitoring systems might be convenient due to the possibility of amortizing the costs within the construction process); (c) the Abstract Selected results collected in the continuous dynamic monitoring of two similar steel-concrete composite bridges are reported in the paper. The investigated bridges, consisting of 4 spans and crossing the Olona River, belong to a motorway serving several provinces of the Lombardy region. After a concise description of the bridges and the monitoring systems, details are given on the software tools developed to process the continuously acquired data within a Statistical Pattern Recognition framework. Subsequently, the dynamic characteristics of the bridges are presented and discussed as well as the results of the first year of monitoring, with special attention being paid to the influence of environmental parameters on the variation of natural frequencies. Finally, the correlation between the dynamic characteristics of the two investigated bridges is briefly addressed. III Fabre Conference: Existing Bridges, Viaducts, and Tunnels: Research, Innovation, and Applications Dynamic testing and monitoring of two similar multi-span bridges Ana Avramova a , Carmelo Gentile a * Department of Architecture, Built environment and Construction engineering (ABC), Politecnico di Milano, Milan, Italy

* Corresponding author. E-mail address: carmelo.gentile@polimi.it

2452-3216 © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Conference 10.1016/j.prostr.2026.06.072