PSI - Issue 44

Mauro Mezzina et al. / Procedia Structural Integrity 44 (2023) 566–573 Mauro Mezzina, Alfredo Sollazzo, Giuseppina Uva/ Structural Integrity Procedia 00 (2022) 000–000

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While the vertical strain balances with the one coming from below, the horizontal strain produces, as effect, an outward thrust: ( ℎ=1 ) = 2 = 2 √ 2 = √ 2 = ( ℎ=1 ) ∙ ℎ 5. Conclusions The problem of the response of masonry buildings subjected to seismic actions was analyzed in the paper, with particular reference to torsional effects. The results obtained showed that the classical simplified approaches adopted by many commercial software for the analysis of masonry buildings, in which the structure is schematized as a set of plane frames connected only at the nodes, can lead to some errors. An approach was shown in the paper in which the walls (with and without openings) are modeled as a box-like assembly in which the vertical elements are connected with continuity at the cornerstones. This assumption has several consequences, which can be summarized mainly as: - a significant reduction in the torsional plane rotation angle as a consequence of an increase in torsional stiffness; where 2 α is the angle between the two stresses ϕ or . When α =90° : ( ℎ=1 ) = � 2 + 2 = √ 2 = Being h the overall height of the cornerstone, the outward thrust is:

- a decrease in the normal stress on the generic wall; - the presence of unbalanced thrust at the cornerstones. References

Nunziante, L., Gambarotta, L., Tralli, A. (2010). Scienza delle Costruzioni . McGraw-Hill Ed. Paulay, T. and Priestley M.J.N. (1992). Seismic design of reinforced concrete and masonry structures , John Wiley and Sons. Paulay T. (1996). Seismic Design for torsional response of ductile buildings. Bullettin of th New Zealand National Society for Earthquake Engineering , Vol. 29, n. 3. Sollazzo, A., Marzano, S. (1988) Scienza delle Costruzioni 2 - Elementi di meccanica dei continui e resistenza dei materiali . UTET, Torino, 1988. Leonhardt, F. Mönnig E. (1976). C.a. & c.a.p.: calcolo di progetto & tecniche costruttive – Vol. 1: Le basi del dimensionamento nelle costruzioni in cemento armato . Milano: Edizioni tecniche.