Pushover analysis of a modern aggregate of masonry buildings through macro-element modelling

Abstract

The masonry building aggregates are a typology of construction typical of historical town centres, where a complex structural system with longitudinal and transversal walls is arranged at different ground and roof levels. Currently, the recuperation of the masonry as a structural solution will depend, in significant part, on its use in the construction of housing blocks, which can present many of the features of a typical building aggregate. The behaviour of this construction typology should be assessed under seismic loads, since it has been shown to be vulnerable to such type of loading. In this work, the case of a modern aggregate of masonry buildings, which is constituted by adjacent buildings at different levels, is studied under simulated seismic loading through nonlinear static (pushover) analysis on a macro-element model idealized for the aggregate. A developed concrete block masonry system is adopted as the structural solution. The aggregate is evaluated regarding its seismic performance by considering three different configurations: a set of dwellings with independent behaviour, a levelled conglomeration of buildings, and an unlevelled aggregate. A comparison between the predicted performances of solutions with unreinforced and truss type horizontally reinforced masonry is made in terms of both base shear-displacement response and damage pattern. The main conclusions are that the structural irregularity in elevation implies loss of displacement capacity, and that the horizontal truss reinforcement allows only qualitatively an improvement of the structural ductility, given a more distributed damage and a higher deformation capacity.