Tracking of Localized Cracks in the Finite Element Analysis of Masonry Walls

Abstract

Macro-models are a common choice for the numerical analysis of large-scale masonry structures. Despite their efficiency in terms of pre-processing and computational cost, these strategies often result in a poor representation of cracking, not properly localized and biased by the finite element mesh orientation. This work presents a remedy to the previous shortcomings through the enhancement of the standard smeared crack approach with a crack-tracking algorithm. The smeared crack approach reduces the computational cost and ensures a computationally efficient analysis of small- and large-scale structures. The crack-tracking algorithm aids the localized representation of cracking and improves the mesh-objectivity of the numerical results. A novel crack-tracking algorithm is introduced allowing the modelling of intersecting and multi-directional cracks, which commonly occur in masonry structures under cyclic loading. At constitutive level, a simple and explicit algorithmic formulation is presented, which includes the description of irreversible deformations into an orthotropic continuum damage model. The proposed numerical model is used to simulate the response of an experimentally tested masonry wall under shear cyclic loading.