ABSTRACT
A model developed for the study of fracture in masonry is extended by including a compression cap to the inelastic failure surface so that compressive failure can be captured and represented. The formulation is based on a piecewise linear yield surface and is in the form of a Linear Complementarity Problem (LCP). Masonry is modelled as a discrete system formed by brick units and mortar interfaces. The brick components are in turn modelled using triangular units while the mortar is modelled as a zero thickness interface. Each triangular unit has two nodes along each of its sides/interfaces but not at the vertex. All inelastic responses are lumped and assumed to occur only at the interface nodes, whereas all elastic responses take place only in the units. The inelastic failure surface for the brick and mortar components are each modelled using a Mohr-Coulomb failure surface with a tension cut-off and a linear compression cap. The constitutive law is a single branch softening law. Results comparing the simulation of an experiment on a shear wall loaded under combined compression and shear is used to verify the formulation.
