A new discrete element model for the evaluation of the seismic behaviour of unreinforced masonry buildings

The evaluation of the nonlinear seismic response of masonry buildings represents a subject of considerable importance whose resolution is nowadays a main research topic in earthquake engineering. Refined nonlinear finite element models require a huge computational cost that makes these methods unsuitable for practical application. In this paper an innovative discrete-element model, conceived for the simulation of the in-plane behaviour of masonry buildings, is presented. The basic idea of the proposed approach is to approximate the in-plane nonlinear response of masonry walls by an equivalent discrete element. This element is able to reproduce the typical in-plane collapse behaviour of a masonry wall subjected to earthquake loading. The reliability of the proposed approach has been evaluated by means of nonlinear incremental static analyses performed on masonry structures, for which theoretical and/or experimental results are available in the literature. The proposed computational strategy provides a relatively simple and practical tool which could be of significant value for the design and the vulnerability assessment of unreinforced masonry structures in seismic areas. (C) 2012 Elsevier Ltd. All rights reserved.