Abstract

This work presents the results of quasi-static non-linear analyses of two masonry buildings using, for the discretization of walls, a macro-element that combines the bending and the in-plane shear responses. The macro-element uses the force-based beam- column element equipped with cross sections discretized in fibers, where the behavior of each fiber is described by uniaxial constitutive models. To describe the shear response of the structural element, the macro-element embeds a shear hinge at mid-span, with a phenomenological non-linear constitutive model calibrated on experimental data. The analyzed buildings are two tangibles examples of un-reinforced and reinforced masonry of the Italian Heritage. The un-reinforced masonry building is a strategic building monitored by the O.S.S., partially damaged by the seismic events in Center Italy in 2016. The reinforced masonry building, a three-storey residential structure, is subject of evaluations carried out in the ReLuis RINTC project, designed as per D.M. 2018.

Abstract

Traditional architecture made of timber-framed masonry (TFM) system is widespread around the world and has already been recognized as a unique cultural heritage to be preserved. These structures have shown a good seismic performance compared to other typologies because their configuration and construction details were constantly updated as soon as the builders addressed the causes of damage mechanisms when earthquakes occurred. Regarding this typology, Romanian TFM structures can be considered a representative example also because they experienced several seismic events showing their good earthquake-resistance. Although these buildings are still constructed and inhabited nowadays, no recommendation is provided in the Romanian building code and its structural behaviour is not properly characterized yet. Bearing in mind that the building’s global response depends on many parameters such as the performance of its structural elements and their interaction, the calibration of shear walls is crucial to define the non-linear behaviour under cyclic loading. A simplified modelling strategy was chosen to simulate TFM wall response consisting of an equivalent frame with linear elastic elements and non-linearities lumped at the joints by using OpenSees. After calibrating the wall response according to the experimental campaign performed at Technical University of Civil Engineering of Bucharest, the panel was adapted to model a representative Romanian TFM building whose dynamic properties were evaluated by eigenvalue analysis and their potential calibration is proposed based on the ambient vibration tests.