PSI - Issue 84

Francesco Cannizzaro et al. / Procedia Structural Integrity 84 (2026) 874–881

881

4. Conclusions This study presents, for the first time, the application of the Discrete Macro-Element Method (DMEM) to the modelling of scour effects in masonry arch bridges. The proposed approach is based on a staged degradation procedure that enables the progressive removal of foundation restraints, thereby simulating the gradual development of the scour hole. This strategy allows the mechanical consequences of scour to be captured within a consistent nonlinear framework, accounting for material nonlinearities. The methodology was validated on a three-span masonry arch bridge model through comparison with previously published finite element results. In particular, the agreement was assessed in terms of selected kinematic response parameters as functions of the normalized scour depth. The comparison demonstrated a satisfactory consistency between the two approaches, confirming the reliability of the proposed DMEM-based modelling strategy. Minor discrepancies were attributed to differences in the modelling approaches. The results highlight a clear relationship between scour depth and modal/kinematic response quantities, such as displacements measures. These findings suggest that measurable kinematic indicators could be effectively correlated with the progression of scour, thus providing a potential basis for structural health monitoring strategies aimed at the indirect assessment of foundation erosion. Overall, the proposed framework demonstrates the capability of DMEM to simulate the complex interaction between scour processes and structural response, paving the way for future developments in performance-based assessment and monitoring-oriented modelling of existing masonry bridges. References Caddemi, S., Caliò, I., Cannizzaro, F., D’Urso, D., Pantò, B., Rapicavoli, D., Occhipinti, G., (2019) 3D discrete macro-modelling approach for masonry arch bridges. IABSE Symposium, Guimaraes 2019: Towards a Resilient Built Environment Risk and Asset Management. Guimaraes (Portugal), March 27-29, 2019. Calio, I., Marletta, M., & Panto, B., 2012. A new discrete element model for the evaluation of the seismic behaviour of unreinforced masonry buildings. Engineering Structures 40, 327-338. Cannizzaro, F., Pantò, B., Caddemi, S., Caliò, I., 2018. A Discrete Macro-Element Method (DMEM) for the nonlinear structural assessment of masonry arches. Engineering Structures 168, 243-256. D.M. 17 gennaio 2018, “Norme Tecniche per le Costruzioni – NTC 2018,” G.U. Serie Generale n.42, S.O. n.8, 20 Feb. 2018. Gazetas, G., 1991. Formulas and charts for impedances of surface and embedded foundations. Journal of Geothecnical Engineering 117, 1363-81. George, J., Menon, A., 2022. Kinematic approach for scour analysis of masonry arch bridges. Engineering Failure Analysis 141, 106703. Hoffmans, G.J.C.M., Verheij, H.J., 2017. Scour manual. Routledge. Invernizzi, S., Lacidogna, G., Manuello, A., Carpinteri, A., AE monitoring and numerical simulation of a two-span model masonry arch bridge subjected to pier scour. Strain 47(s2), 158-169. Melville, B.W., Coleman, S.E., 2000. Bridge scour, Water Resources Publication. Rapicavoli, D., Cannizzaro, F., Caddemi, S., Caliò, I., 2023. Discrete Macro-Element structural assessment of a railway masonry arch bridge subjected to pier settlements. Life-Cycle of Structures and Infrastructure Systems - Proceedings of the 8th International Symposium on Life Cycle Civil Engineering, IALCCE 2023. Milan (Italy), July, 2-6 2023. Richardson, E.V., Davis, S.R., 2001. Evaluating Scour at Bridges – Hydraulic Engineering Circular No. 18. FHWA. Sarhosis, V., Forgàcs, T., Lemos, J.V., 2020. Modelling Backfill in Masonry Arch Bridges: A DEM Approach. Structural Integrity 11, 178-184. Scozzese, F., Ragni, L., Tubaldi, E., Gara, F., 2019. Modal properties variation and collapse assessment of masonry arch bridges under scour action. Engineering Structures 199, 109665. Scozzese, F., Tubaldi, E., Dall’Asta, A., 2023. Damage metrics for masonry bridges under scour scenarios. Engineering Structures 296, 116914. Tòtj, A.R., Orbàn, Z., Bagi, K., 2009. Discrete element analysis of a stone masonry arch. Mechanics Research Communication 36, 469-480. Tubaldi, E., Macorini, L., Izzuddin, B.A., 2018. Three-dimensional mesoscale modelling of multi-span masonry arch bridges subjected to scour. Engineering Structures 165, 486–500. Zampieri, P., Zanini, M.A., Faleschini, F., Hofer, L., Pellegrino, C., 2017. Failure analysis of masonry arch bridges subject to local pier scour. Engineering Failure Analysis 79, 371–384. Zhang, R., Xiong, W., Ma, X., Cai, C.S., 2023. Progressive bridge collapse analysis under both scour and floods by coupling simulation in structural and hydraulic fields. Part I: Numerical solver. Ocean Engineering 273, 113849. Caddemi, S., Caliò, I., Cannizzaro, F., Pantò, B., 2017. New frontiers on seismic modeling of masonry structures. Frontiers in Built Environment 3, 39.