Strength domains and return algorithm for the lumped plasticity equivalent frame model of masonry structures

Assessment of seismic behaviour of heritage masonry buildings using numerical modelling

“…Here, the distinction lies in the orientation of the crack, which is either kept constant, updated in a stepwise manner, or updated continuously [24]. The smeared crack models are practice-oriented due to the limited data required [25]. For example, in the context of macro-modelling, [26] adopted a smeared crack model for the simulation of brick masonry and adobe walls, and [27] used the isotropic rotating crack model to simulate panels with vertically perforated clay units and various types of head and bed joints.…”

A Nonlinear Macroelement Formulation for the Seismic Analysis of Masonry Buildings

“…The beam is composed by the series arrangement of four sub-elements, a 2-node central elastic Timoshenko beam, two nonlinear flexural hinges located at the end nodes of the central element and a nonlinear shear link [1,2]. According to the equilibrated formulation, a basic reference system is introduced removing the rigid body motions from the six-component vector containing the beam nodal displacements.…”

“…The beam element is assumed as clamped at the base, with additional restraint at the top node affecting the rotation; therefore, the element is in double bending condition. Figure 5 shows the pushover response curves for the (a) slender and (b) squat panel, respectively, in terms of base shear versus top displacement, obtained by using the proposed macroelement formulation (square symbols), compared with the experimental envelope curves (triangle symbols) and with the results presented in [2] (circle symbols), where a rigid-perfectly plastic behaviour has been assumed for the hinges. A very good agreement between the experimental envelope curves and those obtained with the proposed macroelement is noted.…”

“…Among the various approaches proposed, macroelement formulations [1,2,3] allow to satisfactorily describe the main global aspects of masonry structural response in a simplified fashion, representing a good compromise between accuracy and computational burden.…”

“…This study presents a macroelement for the nonlinear dynamic analysis of masonry buildings, according to the equivalent frame model [1,2]. This, formulated in a force-based framework, consists of a central linear elastic element, two flexural hinges at the ends and a shear link arranged in series, accounting for the hysteresis under cyclic loads.…”