In-plane behavior of clay masonry walls: experimental testing and finite element modeling

Extensive experimental research aimed at defining the in-plane cyclic behavior of three types of load-bearing masonry walls, assembled with perforated clay units, and various types of head and bed joints was carried out. Experimental behavior was modeled with four types of nonlinear finite-element models. Both macromodeling and micromodeling strategies, implementing either isotropic or orthotropic material laws, were adopted. Two simplified criteria were proposed for calibrating the models, one for defining orthotropic properties starting from perforated unit geometry and the other for defining expanded unit and interface element properties in micromodels. The procedures adopted for model calibration established the reliability of various modeling strategies. Results allow some conclusions to be drawn about the reliability of diagonal compression tests for large unit masonry, the stress distribution and different behaviors of masonry made with different head and bed joints, and the influence of unit strength on the in-plane behavior of masonry.