PSI - Issue 78

Marta Bertassi et al. / Procedia Structural Integrity 78 (2026) 1521–1528

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greater than the elastic period, NTC 2018 generally underestimates spectral ordinates relative to NLTHA, while FprEN 1998 provides closer estimates, with slightly higher values. The simplified NLKA procedures from NTC 2018 and FprEN 1998 were also compared with NLTHA results from experimentally calibrated models. Generally, the kinematic analysis proved conservative in estimating displacement demands and collapse capacity, providing a cautious basis for assessing OOP overturning mechanisms. However, in specific cases involving very slender and heavily loaded walls, the NTC 2018 procedure significantly underestimated displacements and failed to predict the exceedance of the collapse limit state, which was instead captured by NLTHA. As expected from its formulation, FprEN 1998 generally results in higher displacement demands than NTC 2018. It should be noted that this type of geometry is not commonly found in the existing Italian building stock, and the acceleration levels at which these issues were observed were relatively high. These discrepancies may be due to the period shift induced by global inelastic response, which alters the shape and amplitude of the floor response spectrum, as well as the possible retraction of hinges relative to the edges of the rigid blocks forming the kinematic mechanism. Further investigations are necessary to better assess these situations and explore possible strategies for improving the predictive accuracy of NLKAmethods. Acknowledgements This study was conducted within the DPC-ReLUIS 2024 – 2026 project “WP10 – Masonry Construction ”, funded by the Italian Department of Civil Protection (DPC). The views and conclusions expressed in this work are those of the authors and do not necessarily reflect those of the funding entities. References European Committee for Standardisation (CEN), 2025a (Draft). “ Eurocode 8 — Design of structures for earthquake resistance — Part 1-2: Buildings ”. European Standard FprEN 1998-1-2:2025, CEN/TC 250/SC 8, Brussels. European Committee for Standardisation (CEN), 2025b (Draft). “ Eurocode 8 — Design of structures for earthquake resistance — Part 3: Assessment and retrofitting of buildings and bridges ”. European Standard FprEN 1998-3:2025, CEN/TC 250/SC 8, Brussels. Dizhur, D., Ingham, J., Moon, L., Griffith, M., Schultz, A., Senaldi, I., et al ., 2011. Performance of masonry buildings and churches in the 22 February 2011 Christchurch earthquake. Bull N Z Soc Earthq Eng ; 44(4):279–296. https://doi.org/10.5459/bnzsee.44.4.279-296. Giuffrè, A., 1996. A mechanical model for statics and dynamics of historical masonry buildings. In: Petrini, V., Save, M. (eds) Protection of the Architectural Heritage Against Earthquakes . Springer-Verlag: Vienna; p. 71–152. https://doi.org/10.1007/978-3-7091-2656-1_4. Graziotti, F., Tomassetti, U., Penna, A., Magenes, G., 2016. Out-of-plane shaking table tests on URM single leaf and cavity walls. Engineering Structures , 125:455 – 470. https://doi.org/10.1016/j.engstruct.2016.07.011. Sgobba, S., Felicetta, C., Russo, E., D’Amico, M., Lanzano, G., Pacor F., Luzi, L., Baraschino, R., Baltzopoulos, G., Iervolino, I. The online graphical user interface of REXELweb for the selection of accelerograms from the Engineering Strong Motion database (ESM). In: 39° Convegno Nazionale Gruppo Nazionale Geofisica della Terra Solida (GNGTS) , 22–24 June 2021. Available online at https://hdl.handle.net/11588/988455. Ingham, J., Griffith, M., 2011. Performance of unreinforced masonry buildings during the 2010 Darfield (Christchurch, NZ) earthquake. Aust J Struct Eng ; 11(3):207–224. https://doi.org/10.1080/13287982.2010.11465067. Ministry of Infrastructures and Transport (MIT), 2018. Norme Tecniche per le Costruzioni (NTC 2018) . Decree of 17/01/2018, published in the Official Gazette No. 42 of 20/02/2018. MIT, Rome, Italy (in Italian). Ministry of Infrastructures and Transport (MIT), 2019. Istruzioni per l’Applicazione dell’Aggiornamento delle “Norme Tecniche per le Costruzioni”. Circular No. 7 of 21/01/2019. MIT, Rome, Italy (in Italian). Penna, A., Morandi, P., Rota, M., Manzini, C.F., Da Porto, F., Magenes, G., 2014. Performance of masonry buildings during the Emilia 2012 earthquake. Bull Earthq Eng ; 12(5):2255–2273. https://doi.org/10.1007/s10518-013-9496-6. Sorrentino, L., Liberatore, L., Liberatore, D., Masiani, R., 2014. The behavior of vernacular buildings in the 2012 Emilia earthquakes. Bull Earthq Eng ; 12:2367–2382. https://doi.org/10.1007/s10518-013-9455-2. Tomassetti, U., Graziotti, F., Penna, A., Magenes, G., 2018. Modelling one-way out-of-plane response of single-leaf and cavity walls. Engineering Structures . 167:241 – 255. https://doi.org/10.1016/j.engstruct.2018.04.007. Tomassetti, U., Graziotti, F., Sorrentino, L., Penna, A., 2019. Modelling rocking response via equivalent viscous damping. Earthquake Engineering & Structural Dynamics . 48:1277 – 1296. https://doi.org/10.1002/eqe.3182.