PSI - Issue 44

Gaetana Pacella et al. / Procedia Structural Integrity 44 (2023) 1324–1331 Gaetana Pacella et al./ Structural Integrity Procedia 00 (2022) 000 – 000

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analyses and practical solutions suggested. The main considerations emerged from the paper are listed in the following:  Modelling of irregular walls through the EF is not an automatable procedure, but each irregularity should be analyzed case by case as a function of the opening layouts. Once the EF has been defined, a comparison with the results provided by more sophisticated model is of paramount importance to assess the validity of the proposed EF model.  Modelling of the spandrels is still a difficult task. Their behavior is influenced by many parameters (amount of axial force, effectiveness of tensile-resistant elements, material properties, etc.) which can modify significantly the spandrel’s response. Thus, the development of limit schemes can be useful, especially i n engineering practice, to define a range of behavior of the wall.  Flange effect cannot be neglected to develop reliable EF model. The outcomes of the research showed that the connection degree between the orthogonal walls modify the in-plane seismic response of the walls, producing variable increment of base shear depending on effectiveness of the connection between the transverse walls. Acknowledgements This study has been developed also with the financial support of the DPC-Reluis research project 2019-2021, WP10 Aspetti normativi Costruzioni Esistenti in Muratura – Task 10.3 - Validazione/confronto strumenti software per l’applicazione dei metodi di verifica da norma . References Beyer, K., Dazio, A. 2012. Quasi-static cyclic tests on masonry spandrels. Earth Spectra 28(3), 907-929. Calderoni, B., Cordasco E.A., Lenza, P. 2010. Structural behaviour of masonry spandrels of URM buildings subjected to horizontal loading: experimental analysis. Ingegneria Sismica 3(4), 49-68. Calderoni B, Prota A, Cordasco EA, Sandoli A. 2016. Seismic vulnerability of “ancient” masonry buildings and strengthening intervention strategies. 16th Conference IBMAC. Trends, Innovations Challenges. Padua, pp 727-736. Calderoni, B., Cordasco E.A., Musella, C., Sandoli, A. 2017. La modellazione delle pareti murarie in relazione alle irregolarità geometriche: problemi aperti. Proc. of XVII ANIDIS Conference Seismic Engineering in Italy, Pistoia, Italy. Cattari, S., D’Altri, A.M., Camilletti, D., Lagomarsino, S. 2022. Equivalent frame idealization of walls with irregular opening in masonry buildings. Eng Struct 256, 114055. Dolce, M. 1989. Schematizzation and modelli of masonry walls for in-plane actions. Course on rehabilitation of masonry buildings in seismic area. College of Engineers of Potenza (in Italian). ISR 2019 - Italian Seismic Reccomandations n.7/2019. Instruction for the use of technical code for constructions, published by DM17/01/2018. Ministry of Infr. And Transp., Italy. Lagomarsino, S., Penna, A., Galasco, A., Cattari, S. 2013. TreMuri program: an equivalent frame model for the nonlinear seismic analysis of masonry buildings. Eng Struct, 56, 1787-1789. Liberatore D. (Editor). 2001. Progetto Catania, Indagine sulla risposta sismica di due edifici in muratura, GNDT (CNR). Rome, Italy. Ottonelli, D., Manzini, C.F., Marano, C., Cordasco, E.A., Cattari, S. 2022. A comparative study on a complex URM building: part I - sensitivity of the seismic response to different modelling options in the equivalent frame models. Bull of earth Eng 20, 2115-2158. Quagliarini, E., Maracchini, G., Clementi, F. 2017. Uses and limits of the equivalent frame model on existing unreinforced masonry buildings for assessing their seismic risk: a review. J of Build Eng, 10, 166-182. Sajid, H.U., Ashraf, M., Ali, Q., Sajid H.S. 2018. Effects of vertical stresses and flanges on seismic behavior of unreinforced crick masonry. Eng Struct 155, 394-409. Sandoli, A., Musella, C., Lignola G. P., Calderoni, B., Prota, A. 2020a Spandrel panels in masonry buildings: effectiveness of the diagonal strut model within the equivalent frame model . Structures 27; 879-893. Sandoli, A., Pacella, G., Cordasco E.A., Calderoni B. 2021b. PROS and CONS of linear and nonlinear seismic analyses for existing URM structures: Application to a historical building . Structures 32, 532-547. Sandoli, A., Calderoni B. Methodology for an effective retrofitting strategy of existing masonry buildings: a case study near L’Aquila . International Journal of Masonry Research and Innovation, Vol. 6, No2, 2021; 141-165. Sandoli, A., Pacella, G., Lignola G. P., Calderoni, B., Prota, A. 2020b. FRP-reinforced masonry spandrels: experimental campaign on reduced scale specimens . Construction and Building Materials 261; 119965. Sandoli A, Lignola GP, Calderoni B, Prota A. 2021a. Fragility curves for Italian URM buildings based on a hybrid method . Bull of Earthquake Engineering 19(12), 4979-5013. Tomazevic, M., Lutman, M., Weiss, P. 1993. The seismic resistance of historical urban buildings and interventions in their floor systems: an experimental study. The Masonry Soc J, 77-86.