Shear test on fiber reinforced materials
Minor destructive investigation technique that allows the measurement of the shear strength of a reinforcement material (generally FRP or FRCM composite systems) attached to a substrate, through the application of a load parallel to the direction of the substrate. The test is carried out on a free edge of the structure on which the reinforcement is bonded (“direct” type test). The availability of an appropriate free portion of composite material (i.e. unbonded) is required, in continuity with the bonded material. A tensile force is then applied on the unbonded end using the edge of the building as contrast. The adhesion capacity is considered acceptable if at least 80% of the tests (at least two out of three in case of three tests) indicate an ultimate shear force not lower than the 85% of the maximum prescribed design force.
Reference standards: CNR-DT 200 R1/2013; CNR-DT 215/2018.