Issue 51

A. Gesualdo et alii, Frattura ed Integrità Strutturale, 51 (2020) 376-385; DOI: 10.3221/IGF-ESIS.51.27 376 Focussed on Fracture and Damage Detection in Masonry Structures Minimum energy strategies for the in-plane behaviour of masonry Antonio Gesualdo*, Bruno Calderoni University of Naples “Federico II”, Department of Structure for Engineering and Architecture, Napoli, Italy Via Claudio 21, 80125, Napoli, Italy gesualdo@unina.it , http://orcid.org/0000-0002-7063-8064 calderon@unina.it , https://orcid.org/0000-0001-5596-9829 Antonino Iannuzzo ETH Zürich, Institute of Technology in Architecture, Zürich, Switzerland iannuzzo@arch.ethz.ch, http://orcid.org/0000-0002-6633-149X Antonio Fortunato University of Salerno, Department of Civil Engineering, Fisciano (SA), Italy a.fortunato@unisa.it, https://orcid.org/0000-0001-9224-2143 Michela Monaco University of Campania “Luigi Vanvitelli”, Department of Architecture and Industrial Design, Aversa (CE), Italy michela.monaco@unicampania.it, http://orcid.org/0000-0001-7895-7089 A BSTRACT . Unreinforced masonry is the most diffused construction material in the major part of historical centers in Europe. In a building subjected to earthquake forces the contribution of in-plane shear resistance of the masonry walls is a determinant factor for the stability of the whole structure. In particular, the masonry piers are the structural elements subjected to the combination of normal and shear forces. In general, ductile tools to model the in plane behaviour of masonry are always welcome in order to evaluate the capacity of walls subjected to vertical and horizontal actions. In this framework, two no-tension approaches to model the behaviour of masonry walls loaded with in-plane forces, involving a minimum energy procedure, are presented. Both the procedures allow the representation of the stress maps in the panel in case of monotonic increase of shear load. The results of the numerical analyses are compared and discussed. K EYWORDS . Masonry; In-plane loads; Minimum potential energy. Citation: Gesualdo, A., Calderoni, B., Iannuzzo, A., Fortunato, A., Monaco, M. Minimum energy strategies for the in-plane behaviour of masonry, Frattura ed Integrità Strutturale, 51 (2020) 376-385. Received: 28.09.2019 Accepted: 25.11.2019 Published: 01.01.2020 Copyright: © 2020 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. I NTRODUCTION he analysis of masonry structures has been for years a challenging issue to be addressed, especially when seismic actions are involved. Masonry buildings are in fact the main part of historical centers in Italy and in general all over Europe [ 1]. These buildings are a complex arrangement of masonry walls and different structural elements, T