PSI - Issue 78

Gregory Santilli Di Luia et al. / Procedia Structural Integrity 78 (2026) 1513–1520

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6. Conclusions This study began with the application of the multi-level approach envisaged by the Italian guidelines for the multi risk assessment of existing bridges and viaducts, to a bridge located on a main road in Abruzzo region. The bridge studied was found to be inadequate with regard to both static and seismic actions. To conduct a more in-depth assessment, non-linear dynamic analyses were performed, modelling the deterioration of materials to account for the resulting changes in strength, stiffness, and ductility. The results obtained demonstrate how, with an increasing state of degradation of the structure, there is a reduction in terms of structural capacity to withstand the applied actions, a decrease of the element ductility, and a lower dissipative capacity. As observed, degradation over time, without timely remediation of the structure deterioration, leads to a progressive reduction in the safety factor. This aspect is of fundamental importance for particularly degraded structures, as it means that only by accounting for the time-dependent behaviour induced by degradation can the actual capacity of the structure at the moment of verification be identified and its remaining service life estimated. Acknowledgements This study was supported by FABRE – “Research consortium for the evaluation and monitoring of bridges, viaducts and other structures” (www.consorziofabre.it/en). Any opinion expressed in the paper does not necessarily reflect the view of the funder. References Andrade, C., & Alonso, C. (1996). "Corrosion rate monitoring in the laboratory and on-site." Construction and Building Materials, 10(5), 315 – 328. ANSFISA, 2022. Istruzioni Operative per L’applicazione delle Linee Guida per la Classificazione e Gestione del Rischio, la Va lutazione della Sicurezza ed il Monitoraggio dei Ponti Esistenti. Bertolini, L., Elsener, B., Pedeferri, P., & Polder, R. (2013). Corrosion of Steel in Concrete: Prevention, Diagnosis, Repair. Wiley-VCH. Biondini, F. & Vergani M. (2012). Damage modeling and nonlinear analysis of concrete bridges under corrosion.S. Yang, S. Zheng, L. Liu, L. Dong, W. Zhao, Y. Xiao. Seismic analysis model of corroded reinforced concrete columns considering corrosion damage and shear response. Construction and Building Materials 483 (2025). Di Sarno, L., & Pugliese, F. (2020). Numerical evaluation of the seismic performance of existing reinforced concrete buildings with corroded smooth rebars. Bulletin of Earthquake Engineering, 18(9), 4227 – 4273. EN 1992-1-1:2004 – Eurocode 2: Design of concrete structures – Part 1-1: General rules and rules for buildings. Fib Bulletin 34 (2006) Model Code for Service Life Design MIT, Ministero delle Infrastrutture e dei Trasporti, 2020. Linee Guida per la Classificazione e Gestione del Rischio, la Valutazione della Sicurezza ed il Monitoraggio dei Ponti Esistenti. NTC2018. Decree 17/01/2018, n. 42. Adjournment of «Technical Code for Constructions», Italian ministry of infrastructures and transports (NTC18). In Italian language; n.d. Papadakis, V.G. (1999). Effect of supplementary cementing materials on concrete resistance against carbonation and chloride ingress. Papadakis, V.G., Vayenas, C.G., & Fardis, M.N. (1991). "Fundamental modeling and experimental investigation of concrete carbonation." ACI Materials Journal, 88(4), 363 – 373. Salvatore, W., Uva, G., Venanzi, I., Mazzotti, C., Morici, M., Natali, A., Dall’Asta, A., Ubertini, F., Mannella, P., Lepori, L., Pellicanò, F., Calò, M., Cardillo, E., Nettis, A., Bencivenga, P., Brando, G., Borlenghi, P., Carbonari, S., Clemente, P., … Proverbio, E. (2024). Application of Italian Guidelines for structural-foundational and seismic risk classification of bridges: The Fabre experience on a large bridge inventory. Procedia Structural Integrity, 62, 1–8. Taucer, F. F., Spacone, E., & Filippou, F. C. (1991). A fiber beam-column element for seismic response analysis of reinforced concrete structures. Tuutti, K. (1982). Corrosion of Steel in Concrete, CBI Research, Sweden.