PSI - Issue 78

Alessia Furiosi et al. / Procedia Structural Integrity 78 (2026) 753–760

760

both the base and the vertical boundary interfaces. Overall, the SUB-D model yielded comparable results to those obtained with more detailed discretization, such as the SUB-R and SUB-V models. However, this modeling approach required significantly lower computational effort. Therefore, the use of a deformable continuum block can be considered a reliable and efficient modeling strategy for capturing the global response of masonry arch bridges, ensuring an optimal balance between computational efficiency and the accuracy of numerical outcomes. 5. Conclusions This paper presented a numerical investigation into the seismic behavior of a masonry arch bridge inspired by a real structure located in Northern Italy, employing the Distinct Element Method. Three-dimensional numerical models were developed, incorporating both rigid and deformable blocks. The masonry components were modeled as rigid blocks with zero-thickness interfaces governed by a Mohr-Coulomb contact law, while the backfill material was represented using three alternative strategies: a deformable continuum block, a rigid block assembly, and a Voronoi based discretization. Quasi-static analyses were conducted by imposing displacement-controlled loading in multiple directions. The simulations captured key failure mechanisms, including hinge formation within the arch and out-of plane overturning of the spandrel walls. he three alternative backfill models exhibited consistent response trends, showing comparable damage mechanisms and force–displacement curves. The findings contribute to a better understanding of the seismic response and failure modes of masonry arch bridges subjected to lateral loading. This work forms part of a broader research effort aimed at improving the seismic assessment procedures for existing The presented study was partly developed within the activities of the 2022-2023 and 2024-2026 ReLUIS-DPC and EUCENTRE-DPC research programs, funded by the Italian National Department of Civil Protection (DPC). The opinions and conclusions expressed by the authors do not necessarily reflect those of the funding entity. The authors express their gratitude to the Itasca Educational Partnership (IEP) Program and Harpaceas S.R.L. References Cundall, P.A., Hart, R.D., 1992. Numerical modelling of discontinua. Engineering Computations 9, 101–113. Damiani, N., DeJong, M.J., Albanesi, L., Penna, A., Morandi, P., 2023. Distinct element modeling of the in ‐ plane response of a steel ‐ framed retrofit solution for URM structures. Earthquake Engineering & Structural Dynamics 52(10), 3030-3052. DOI: 10.1002/eqe.3910 Di Sarno, L., da Porto, F., Guerrini, G., Calvi, P.M., Camata, G., Prota, A., 2019. Seismic performance of bridges during the 2016 Central Italy earthquakes. Bull Earthquake Eng 17, 5729–5761. DPC-RELUIS, 2022-23. WP3 Affidabilità Delle Strutture Esistenti. Task 3 Affidabilità Sismica Dei Ponti Esistenti. Furiosi, A., Damiani, N., Rota, M., Penna, A., 2025. Seismic fragility assessment of a multi-span masonry arch bridge using a discontinuum modeling approach. Earthquake Engineering & Structural Dynamics 54(13), 3320-3340. DOI: 10.1002/eqe.70029. Heyman, J., 1995. The Stone Skeleton: Structural Engineering of Masonry Architecture. Cambridge University Press, Cambridge. Itasca Consulting Group Inc., 2024. 3DEC. Three Dimensional Distinct Element Code. Itasca Software 9.3 documentation . Melbourne, C., Wang, J., Tomor, A.K., 2007. A new masonry arch bridge assessment strategy (SMART). Proceedings of the Institution of Civil Engineers - Bridge Engineering 160, 81–87. MIT. Decreto Ministeriale 17 gennaio 2018: Aggiornamento delle Norme tecniche per le costruzioni. Ministero delle Infrastrutture e dei Trasporti, Rome, Italy (in Italian). Oliveira, D.V., Lourenço, P.B., Lemos, C., 2010. Geometric issues and ultimate load capacity of masonry arch bridges from the northwest Iberian Peninsula. Engineering Structures 32, 3955–3965. Page, J., 1993. Masonry arch bridges, State-of-the-art review (Transport Research Laboratory). HMSO, London. Pelà L., Aprile A., Benedetti A., 2013. Comparison of Seismic Assessment Procedures for Masonry Arch Bridges. Construction and Building Materials 38, 381–394, Pulatsu, B., Erdogmus, E., Lourenço, P.B., 2019. Simulation of masonry arch bridges using 3D discrete element modeling. Structural Analysis of Historical Constructions: An Interdisciplinary Approach, 871-880. Sarhosis, V., Forgács, T., Lemos, J.V., 2020. Modelling Backfill in Masonry Arch Bridges: A DEM Approach, in: Arêde, A., Costa, C. (Eds.), Proceedings of ARCH 2019. Springer International Publishing, Cham, pp. 178–184. Saygılı, Ö., Lemos, J.V., 2021. Seismic vulnerability assessment of masonry arch bridges. Structures 33, 3311–3323. Torre, C., 2003. Ponti in Muratura. Dizionario Storico-Tecnologico. ALinea Editrice, Firenze. masonry arch bridges. Acknowledgements