PSI - Issue 84

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ScienceDirect

Procedia Structural Integrity 84 (2026) 1071–1078

© 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: Masonry tunnel linings; Structural assessment; Kommerell; Arch thrust line; Tunnel Refurbishment. Abstract Before reinforced concrete was used, tunnel linings were constructed using masonry. These linings were designed using graphical static methods, supplemented by empirical observations and experience. The structural assessment of aging masonry structures and infrastructure requires a deep understanding of the historical design assumptions that shaped their geometry and load-carrying mechanisms. In this way it is possible to carry out a more accurate assessments and better target the retrofit strategies for heritage masonry tunnels. This paper describes the primary methods historically used in Italy for designing masonry tunnel linings and provides a comparative analysis of two prominent historical approaches that are then applied to a highway tunnel built in the mid 1930s, for which the soil and masonry have been thoroughly characterized. The results of the two theoretical approaches are discussed and then compared with in situ stresses measured using flat-jacks, to determine which method best approximated the experimental results. III Fabre Conference: Existing Bridges, Viaducts, and Tunnels: Research, Innovation, and Applications A comparison of arch-thrust line methods used in the past for designing masonry tunnel linings Gerardo Sorrentino a , Alessandro Borghi a , Marialorenza Vescovi b , Lapo Baccolini c , Manlio Culotta c , Stefano Gazzola c , Bernardino Chiaia a , Daniele Ferretti b , Erica Lenticchia a, * a Politecnico di Torino, Department of Structural, Geotechnical and Building Engineering (DISEG), Corso Duca degli Abruzzi 24, Torino, 10129, Italy b University of Parma, Department of Engineering and Architecture, Via delle Scienze, 181/A, Parma, 43124, Italy c Tecne Gruppo Autostrade per l’Italia S.p.A., Viale Fulvio Testi 280, Milano, Italy

* Corresponding author. Tel.: +39 0110904863. E-mail address: erica.lenticchia@polito.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.2026.06.137