Equivalent frame discretisation for URM façades with irregular opening layouts

Abstract Researchers and practitioners widely employ simplified Equivalent Frame Models (EFM) for reproducing the in-plane governed response of unreinforced brick masonry (URM) structures, as they typically represent an acceptable compromise between numerical accuracy computational cost. However, when considering URM structural systems with irregular opening distribution, definition effective height length deformable components (i.e. pier spandrel elements) still represents open challenge. In this work, influence distribution openings on predicted lateral full-scale façades was investigated. To end, several geometrical combinations characterised by various degrees irregularity were considered idealised according to commonly employed EF discretisation approaches. Then, after a preliminary calibration process against experimental tests both individual piers building façade, EFM results compared micro-modelling predictions, carried out within framework Applied Element Method used benchmark. Although in specific configurations using some approaches, macro micro-models converge similar results, non-negligible differences terms initial stiffness, base-shear damage observed other schemes or layouts, thus indicating that careful selection appropriate criteria is indeed needed performing analyses distributions. Finally, inferred simulated data, potential solutions are given overcome typical issues better approximate outcomes.