A specific rigid element approach is proposed for the in-plane dynamical analysis of masonry walls, whose seismic performance is strongly related to mechanical deterioration and hysteretic energy dissipation. Since the execution of effective time-history analysis necessitates the use of discrete models with reduced number of degrees of freedom, the tricky issue lies in achieving a balance between accuracy in the geometrical description and the need for a realistic damage material model. For this reason, a mechanistic ``rigid body spring model'' RBSM was adopted, which consists of a collection of plane quadrilateral rigid elements connected to each other by two normal springs and one shear spring at each side. The material model was based on a phenomenological description of the cyclic response of masonry, and specific separate hysteretic laws were assigned for the axial and shear deformation between the elements. This separation led to a large reduction in computational effort, though a Coulomb-like law was adopted in order to relate the strength of the shear springs to the vertical axial loading. The effective performance of the present approach is demonstrated by the numerical validation and by comparisons with some well-known experimental and numerical tests presented in the literature

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SUMMARY The paper proposes a systematic comparison between two methods of analysis that are well established in the field of earthquake engineering: nonlinear dynamic analysis and nonlinear static procedure (NSP), applied to the out‐of‐plane seismic response of two masonry façades representative of many ancient Italian churches. The comparison is based on extensive numerical analyses, which focus on the flexural and torsional mechanisms, while the in‐plane damage mechanisms and the possible detachment between the façade and the lateral walls because of a poor connection have been presently disregarded. The computations, both in the static and in the dynamic field, are based on a rigid body and spring model specifically implemented for this issue, computationally efficient and equipped with a realistic model of damage and hysteresis at the mesoscale. An innovative aspect of this study is the heuristic modelling of three‐wythe masonry, to include some typical texture effects on the macroscale nonlinear response. For each façade, two different masonry textures were considered, performing extensive dynamic analyses that offered a detailed overview about the performance under earthquakes of different intensities. In parallel, NSP and the classical N2‐based seismic assessment were applied. A critical discussion and comparison of the results of the two methods is presented to rationally appraise limits and opportunities. In particular, flexural and twisting out‐of‐plane mechanisms were clearly appraised in the dynamic field, whereas NSPs were not always able to describe the collapse, because they missed the partial failures determined by higher vibration modes, as could be expected. Copyright © 2012 John Wiley & Sons, Ltd.