A new discrete macro-element in an analytical platform for seismic assessment of unreinforced masonry buildings

This paper proposes a practice-oriented platform for numerical simulation of Unreinforced Masonry (URM) buildings. It is based on introducing a new two-dimensional discrete model compatible with most existing structural analysis softwares. The proposed platform comprises of two individual two-dimensional macro-elements, a basic macro-element for modeling the piers and spandrels and a rigid-interface macro-element for modeling the nodal regions. A complete set of constitutive equations and behavioral specifications is proportionally characterized and discussed for the basic macro-element based on its phenomenology and the past experimental studies. The proposed approach provides a rather simple and efficient platform for linear or nonlinear static and dynamic analyses by considering the in plane behavior of the URM panels. The validation of the proposed analytical platform is conducted using the results of the past experimental tests on a considerable number of piers, spandrels and a perforated wall. The comparisons indicate that the predicted failure mode and hysteretic behavior as well as the ultimate strength and displacement capacity of these specimens are in a satisfactory agreement. In particular, derivation and interpretation of the results in the proposed approach are straightforward and simple; hence, engineers can use this approach for seismic design or retrofit studies. The proposed platform can be further developed and effectively used for modeling a large building or numerous buildings. (C) 2017 Elsevier Ltd. All rights reserved.