PSI - Issue 84

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ScienceDirect

Procedia Structural Integrity 84 (2026) 1127–1135

© 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 Keywords: Concrete arch bridge; Experimental investigations; Intervention methodologies. This paper presents the outcomes of a series of activities carried out on existing arch bridges belonging to the national road and motorway network. These activities included visual inspections, in-situ and laboratory experimental investigations, as well as analytical assessments of structural safety levels. The main issues encountered are discussed—often related to concrete deterioration and original construction deficiencies—as well as the design strategies adopted for structural strengthening and retrofitting, with particular attention paid to preserving the original identity of the structures. III Fabre Conference: Existing Bridges, Viaducts, and Tunnels: Research, Innovation, and Applications “Concrete Arch Bridges – Experimental Investigations and Intervention Methodologies” L.Fieno a, *, V.Agostini b , M.A.Nasta b , L.Piselli b , S.Tiero b , M.P.Petrangeli c a Engineer, CEO, TD, and Partner of “Mario Petrangeli & Ass. S.r.l” b Structural Enginee of “Mario Petrangeli & Ass. S.r.l.” a Professor, Engineer and President of “Mario Petrangeli & Ass. S.r.l” Abstract After World War II numerous concrete arch bridges were built in Italy, many of which feature a deck-above structural scheme, commonly referred to as the "Maillart type," named after the Swiss engineer Robert Maillart, a pioneer of this structural typology. These bridges, characterized by a strong integration between structural form and architectural function, still represent a highly valuable engineering heritage. Another significant category includes deck-below arch bridges with concrete hangers, which are also widespread across the Italian infrastructure network.

* Corresponding author. Tel.: +39-348-494-8305 E-mail address: luigi.fieno@mpaing.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.2026.06.144