Simplified two-step homogenization model for full scale FRCM reinforced masonry panels out-of-plane loaded

The paper deals with the analysis of two series of full scale masonry panels by means of a simplified homogenization approach formulated by the authors [1]. The experimental campaign, which is briefly discussed in the present paper, has been conducted by Nanni and co-workers at the University of Miami [3][4] testing twelve panels constructed adopting two different running bond masonry supports: clay bricks and concrete units. Homogenization is performed through a two-step procedure where the elementary cell is discretized by means of 24 CST elastic elements (bricks) and joints are reduced to interfaces with holonomic softening behavior. At a structural level, the masonry is modeled with rigid elements and homogenized flexural and torsional springs. In order to further validate the homogenization model proposed, a sophisticated tri-dimensional heterogeneous micro-modeling technique is also used. The Fabric Reinforced Cementitious Matrix (FRCM) composite material adopted to strengthen half of the tested walls has been modeled by means of truss elements whose mechanical properties have been calibrated to properly account for the behavior of the textile embedded into the cementitious binder. The accuracy of the proposed model, as well as the computational effort required to complete the analyses, have been evaluated with respect to the numerical and experimental outcomes.