A simplified model to estimate the contribution of EB-FRP to the shear strength of masonry panels

The application of Externally Bonded Fibre-Reinforced Polymers (EB-FRPs) for improving the shear strength of masonry panels still presents some open issues, related to its testing and analysis. In fact, tests of in-plane reinforced masonry show an ample variability, due to the number of possible masonry units, textures and structures, types of external FRPs, reinforcement application patterns, and experimental setups. This work has been focused on the collection of diagonal compression tests available in literature, and aims at proposing a procedure to assess an empirically-based simplified formulation of the shear strength improvement provided by EB-FRPs. Shear strength of unreinforced masonry is estimated with the Turnšek-Čačovič expression, while the contribution of EB-FRP is computed empirically on the basis of effectiveness curves. This simplified formulation might be an alternative way to those based on fracture mechanics of FRP-to-substrate bond behaviour, which is still far from being exhaustively investigated in the case of masonry.