A macro-element modelling technique to account for IP and OOP interactions in URM infilled RC or steel building

Buildings with unreinforced masonry (URM) infills is a common construction practice worldwide. To correctly assess the seismic performance of such structures, the analysis of the masonry infills under in-plane (IP) and out-of-plane (OOP) loading, as well as their interaction, is essential. The aim of this paper is to present a new macro-element modelling technique able to simulate the IP and OOP response of URM infilled frames subjected to earthquakes. The model consists of a horizontal, a vertical and two diagonal struts represented by fiber section beam-column elements. The compressive behavior of the struts are defined by empirical strength and strain parameters. The paper also discusses on derivation of the empirical parameters based on the actual properties of infill wall. The proposed macro-element model has been validated with experimental results available in the literature. From the numerical analysis, a good agreement between the experimental and numerical results was obtained.