Experimental characterization of glass and carbon FRCMs for masonry retrofitting

In the last decade, Fibre Reinforced Cementitious Matrix (FRCMs) became an interesting inorganic alternative to the widespread organic-based Fibre Reinforced Polymers (FRPs). FRCMs are more appealing as retrofitting materials for masonry structures thanks to their generally better compatibility to existing masonry substrates, especially when lime-based matrices are used. In this framework, two FRCMs were tested to evaluate their tensile and shear bond mechanical behaviours, when applied to brick masonry prisms. One FRCM was made of a hydraulic lime mortar coupled with an alkali-resistant glass fibre mesh, while the other was made of a latex-modified cement mortar coupled with a carbon mesh. Tensile tests and single lap shear tests were performed to characterize the relevant strengths of the two FRCMs. The objective was the definition of the basic design parameters for the appraisal of the two FRCMs as strengthening inorganic composite materials for masonry structures. In this paper, the experimental results will be presented and discussed with the definition of the tensile and bond design strengths of the two FRCMs. An example of application with related normalized cost estimations is also provided; it showed that the best trade-off of mechanical performance and cost-effectiveness was given by the carbon mesh FRCM.