PSI - Issue 44

Stefano Bracchi et al. / Procedia Structural Integrity 44 (2023) 442–449 Stefano Bracchi, Maria Rota, Andrea Penna / Structural Integrity Procedia 00 (2022) 000–000

449

8

and characterized by absence or presence of openings in the walls orthogonal to the direction of the seismic action, were studied. Nonlinear static analyses were carried out on the entire tridimensional models and on a series of single wall models, defined according to the previously developed modelling strategy and characterized by different length of the portion of flange modelled. Different macroelements, implemented in the TREMURI software, based on the equivalent-frame modelling technique, were adopted. Some of them are code-compliant, others represent refined mechanics based elements. A comparison of the results obtained from the analysis of the entire building and the analysis of single walls was carried out, with a focus on the influence of the different macroelements adopted. Results obtained highlighted that increasing the portion of flange modelled, the results of the single wall analysis (modelled adopting the developed strategy) tends to the results obtained for the same wall, belonging to the entire building. This is true when the refined macroelement of Penna et al. (2014) and Bracchi et al. (2021) are used, whereas this trend is not always present when the code-compliant bilinear element is adopted. This work allows to conclude that, when building are characterized by flexible floors, the single wall analysis can be performed. However, to obtain meaningful results, it is necessary to model all the aspects influencing the response, following the developed strategy, in particular modelling also the contribution of flanges. The length of flanges to be modelled to obtain the best results is equal to half of the transversal walls, in case the transversal walls have no openings, and to the length up to the opening, in case openings are present in the transversal walls. The strategy developed to perform single wall analysis, which was tested only with reference to buildings with rigid floor, has recently been applied to perform nonlinear analyses of a historic URM buildings with flexible floors, in the framework of the study of the seismic vulnerability of existing URM buildings (Lagomarsino et al. 2022). Acknowledgements This work was carried out within the framework of the ReLUIS Projects 2019-21 and 2022-24 - WP10: Code contributions for existing masonry constructions, funded by the Italian Department of Civil Protection. References Bracchi, S., Galasco, A., Penna, A., 2021. A novel macroelement model for the nonlinear analysis of masonry buildings. Part 1: axial and flexural behavior. Earthquake Engineering and Structural Dynamics 50(8), 2233-2252. Bracchi, S., Penna, A., 2021. A novel macroelement model for the nonlinear analysis of masonry buildings. Part 2: shear behavior. Earthquake Engineering and Structural Dynamics 50(8), 2212-2232. Lagomarsino, S., Penna A., Galasco, A., Cattari, S., 2013. TREMURI program: An equivalent frame model for the nonlinear seismic analysis of masonry buildings. Engineering Structures 56, 1787-1799. Lagomarsino, S., Cattari, S., Angiolilli, M., Bracchi, S., Rota, M., Penna, A., 2022. Modelling and seismic response analysis of existing URM structures. Part 2: historical buildings. Journal of Earthquake Engineering, https://dx.doi.org/10.1080/13632469.2022.2087800. Magenes, G., Penna, A., Galasco, A., Rota, M., 2010. Experimental characterisation of stone masonry mechanical properties, Proceedings of the 8th International Masonry Conference, Dresden, Germany. Magenes, G., Penna, A., Rota, M., Galasco, A., Senaldi, I., 2014. Shaking table test of a strengthened full-scale stone masonry building with flexible diaphragms. International Journal of Architectural Heritage 8(3), 349–375. MIT Ministry of Infrastructures and Transport (2008). D.M. 14 Gennaio 2008 - “Nuove Norme Tecniche per le Costruzioni”, S.O. n.30 alla G.U. del 4.2.2008, No. 29. MIT Ministry of Infrastructures and Transport (2019). Circ. C.S.Ll.Pp. No. 7 of 21/1/2019: ‘‘Istruzioni per l’applicazione dell’«Aggiornamento delle “Norme tecniche per le costruzioni”» di cui al decreto ministeriale 17 gennaio 2018’’. Consiglio superiore dei lavori pubblici. S.O. n.5 alla G.U. del 11.2.2019, No. 35. Penna, A., Lagomarsino, S., Galasco, A., 2014. A nonlinear macroelement model for the seismic analysis of masonry buildings. Earthquake Engineering Structural Dynamics 43(2), 159-179. Penna, A., Senaldi, I.E., Galasco, A., Magenes, A., 2016. Numerical simulation of shaking table tests on full-scale stone masonry buildings. International Journal of Architectural Heritage 10(2-3), 146-163. Turnšek, V., Sheppard, P., 1980. The shear and flexural resistance of masonry walls, Proceedings of the International Research Conference on Earthquake Engineering, Skopje, Macedonia.