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 equa-tions and behavioral specifications is proportionally characterized and discussed for the basic macro-element based on its phe-nomenology and the past experimental studies. The proposed approach provides a rather simple and efficient platform for line-ar or nonlinear static and dynamic analyses by considering the in-plane behavior of the URM panels. The validation of the pro-posed analytical platform is conducted using the results of the past experimental tests on a considerable number of piers, span-drels and a perforated wall. The comparisons indicate that the predicted failure mode and hysteretic behavior as well as the ul-timate strength and displacement capacity of these specimens are in a satisfactory agreement. In particular, derivation and in-terpretation 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.
Alireza Aghababaie M.