PSI - Issue 84

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ScienceDirect

Procedia Structural Integrity 84 (2026) 874–881

© 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 Abstract Scour is usually a hidden cause of loss of capacity in bridges associated with the excavation of material around the foundations of piers or abutments due to the erosive action of floods. Piers’ rotation, settlements and loss of global capacity to vertical loads are the main consequences of scour. Foreseeing the structural behaviour of a bridge in presence of scour is crucial to adequately assess its robustness and residual capacity. In this regard, the availability of fast and reliable tools to evaluate with a reasonable computational cost the effect of scour in bridges is a need of road and rail network operators. This study extends the framework of the Discrete Macro-Element Model (DMEM) to model scour in masonry arch bridges. The DMEM is a modelling strategy based on an equivalent mechanical scheme able to simulate with few degrees of freedom the main failure mechanisms of a masonry portion. Originally proposed for the in-plane behaviour of masonry walls, subsequent expansions of its modelling capabilities led to the possibility to simulate the nonlinear behaviour of masonry arch bridges under static and seismic conditions. In this study, a staged degradation procedure to simulate the progressive erosion of material at the base of piers was added as a further feature of the DMEM. To this aim, scour is modelled as a progressive removal of the restraints according to a given shape of the scour hole and to its expected evolution. The proposed procedure is duly validated in terms of meaningful response parameters with results available in the literature obtained with more refined numerical approaches. III Fabre Conference: Existing Bridges, Viaducts, and Tunnels: Research, Innovation, and Applications Modelling scour in masonry arch bridges with the Discrete Macro Element Model Francesco Cannizzaro a, *, Davide Rapicavoli a , Enrico Tubaldi b a Department of Civil Engineering and Architecture, University of Catania, via Santa Sofia 64, Catania 95125, Italy b Department of Civil and Environmental Engineering, University of Strathclyde, 75 Montrose Street, Glasgow G1 1XQ, UK

* Corresponding author: E-mail address: francesco.cannizzaro@unict.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.2026.06.112