Flemish bond brickwork: Macroscopic elastic properties and nonlinear behaviour

Assuming Flemish bond brickwork to be periodic, a finite element model of a Representative Volume Element (RVE) is developed to predict its macroscopic behavior using a homogenization approach. In linear elasticity, the numerical results are used to assess the reliability of recently proposed closed-form expressions for the macroscopic elastic properties (Taliercio, 2018). Assuming that both mortar and units experience plastic strains and damage effects, the macroscopic strength domain under in-plane principal stresses parallel to the joints is identified and compared with that predicted by Drougkas et al. (2016). Eventually, the model is applied to predict the homogenized strength of Flemish bond brickwork under elementary macroscopic in-plane stresses and transverse shear. The effect of the collar joint on the macroscopic response is pointed out by comparing the numerical results with those obtained on header bond brickwork. This effect is shown to be particularly significant under horizontal, transverse shear.