Modelling reinforced masonry buildings by a mechanics-based macroelement approach

Abstract

The seismic behaviour of unreinforced masonry (URM) buildings is frequently modelled using macroelements, in the framework of an equivalent-frame schematisation of the walls. Although the advantages of this modelling technique, mainly related to the compromise between computational burden and accuracy of the results, appear to be valid also in the case of reinforced masonry (RM) buildings, few attempts have been made to extend its applicability to RM. This work proposes a mechanics-based macroelement approach to simulate the in-plane nonlinear response of RM piers, starting from a macroelement model widely adopted for URM and implemented in the TREMURI software. The strategy consists of discretising a masonry pier into sub-macroelements, representative of masonry and horizontal reinforcement, with nonlinear beams representing vertical reinforcement. Experimental tests performed on clay blocks RM piers were simulated to test the efficiency of this model in capturing the strength and cyclic behaviour associated with different damage mechanisms. More complex structures were then studied, starting from assemblies of piers, up to entire buildings. Even in these cases, the modelling approach proved to be able to model the nonlinear cyclic behaviour. Finally, the model was used to compare the response of two buildings in their unreinforced and reinforced configurations, through nonlinear static and dynamic analyses.