Simulating masonry wall behaviour using a simplified micro-model approach

In this paper, a simplified micro-model approach utilising a combination of plasticity-based constitutive models and the extended finite element method (XFEM) is proposed. The approach is shown to be an efficient means of simulating the three-dimensional non-linear behaviour of masonry under monotonic in-plane, out of plane and cyclic loads. The constitutive models include surface-based cohesive behaviour to capture the elastic and plastic behaviour of masonry joints and a Drucker Prager (DP) plasticity model to simulate crushing of masonry under compression. The novel use of XFEM in simulating crack propagation within masonry units without initial definition of crack location is detailed. Analysis is conducted using standard finite element software (Abaqus 6.13) following a Newton Raphson algorithm solution without employing user-defined subroutines. The capability of the model in terms of capturing non-linear behaviour and failure modes of masonry under vertical and horizontal loads is demonstrated via comparison with a number of published experimental studies.