Modelling micro-structure aspects of masonry walls by a simplified approach

Abstract

A specific simplified rigid element approach is proposed to model the elasticplastic behaviour of masonry walls subjected to in-plane loadings. This proposal originates from the consideration that the evaluation of seismic vulnerability of masonry monuments requires peculiar procedures since their responses to earthquakes often differ substantially from those of ordinary buildings. In particular, the effective characterisation of the masonry material requires a special attention because the global mechanical behaviour of this composite material depends strongly on the different textures, as well as on the elastic-plastic characteristics of the component materials. Numerical analyses are made with the objective of evaluating the importance of the micro-structure effects in the response of masonry walls with special attention to the fact that mechanical degradation tends to concentrate in the weaker component according to a well defined pattern. The paper is limited to the case of monotonic loadings as a first step in the formulation of a rigid element model that is suitable for performing complete dynamical analyses.