Understanding the tensile behaviour of masonry parallel to bed joints : a numerical approach

The lack of experimental data for the complete characterisation of the inelastic behaviour of masonry is a key issue in numerical modelling of masonry structures. A solution to obtain the material properties of masonry at the macro-level is to derive them on the basis of the geometrical and material properties of the underlying constituents, namely unit and mortar (micro-level). An interface model for the joints and cracks in the units, which includes a tension cut-off and the Coulomb friction law with variable dilatancy, is used to show that the macro-behaviour of masonry under tension parallel to the bed joints can be effectively predicted. The obtained stress/displacement response measures the fracture energy of masonry (that is the area under the curve, including the descending branch) and can be used as a material property for macro-models, where a relation is established between average masonry stresses and average masonry strains. 22 refs.