Shear strengthening of masonry walls with inorganic-based composites: Quantifying fiber exploitation through a numerical approach

One of the main innovations in the field of structural retrofitting of masonry walls has been the use of inorganic-based composite systems, once it was noticed that they are: compatible with historic substrates, durable, and fire-resistant. In fact, by means of experimental studies, the in-plane behavior of the system has been improved effectively. Nevertheless, the exploitation factor - understood as the ratio between the actual contribution of the strengthening system and the theoretical maximum capacity - is still unclear, especially from the theoretical point of view. The present work reports on extensive numerical research of the exploitation factor related to the use of inorganic-based systems in strengthening the in-plane masonry walls. The effort is mainly concentrated on fabric-reinforced cementitious matrix/mortar (FRCM), composite reinforced mortar (CRM), and steel reinforced grout (SRG) systems, to verify the reliability of existing design-oriented formulations. Finite element models (FEMs) were set up to depict the non-linear behavior of masonry walls under in-plane shear loading. The FEMs also included the detailed depiction of the masonry units, mortar joints, and strengthening layers (i.e. matrix and fabric/mesh/textile). After the models were calibrated properly by using their own experimental data, a collection of parametric studies was performed with the aim of investigating the impact of textile type, matrix properties, and application configurations on the exploitation factor. According to the findings, the exploitation factor depends relevantly on the mechanical compatibility of the matrix. • FEMs concerning the shear strengthening of masonry panels with different inorganic-matrix-based systems. • Experimental versus numerical calibration in terms of global shear stress-strain behavior. • Numerical versus analytical comparison in terms of the fabric’s exploitation level.