Experimental evaluation of elastic shear components for masonry in a Cosserat Continuum

The current research proposes an experimental methodology to evaluate masonry pure shear components, with a particular focus on the validation of the Cosserat or micropolar model by adopting small-scale specimens. The Cosserat continuum model's ability to represent rich media or textures is well-defined in the literature and ideal for characterizing anisotropic materials such as masonry. The experimental validation is proposed using specimens derived from the REV (Representative Elementary Volume) at the micro-scale. This is realized by introducing mortar head joints to the standard triplet specimen, where two periodic masonry textures, the running and the stack bond (limit cases defining perfect and no overlap), are defined. These specimens are tested in two configurations, first simulating shear along the bed joints and second along the head joints, illustrating orthotropic shear configurations of a Cosserat model.