An experimental investigation on shear behaviour of RC T-beams strengthened with CFRP using photogrammetry

This paper reports the results of a series of tests on timber joints strengthened with near-surface mounted (NSM) pultruded fibre-reinforced polymer (FRP) composite strips. Single-shear FRP-to-timber joints are used to investigate the bonded interface with the test variable being the length of bonded plate. Results include (i) joint behaviour and strength, (ii) load-slip responses, (iii) failure modes, and (iv) FRP plate strains as well as plate efficiencies. An effective bond length is also observed and quantified. Up to 61% of the strain capacity of the plate is utilised and this exceeds a plate utilisation of 24% as measured from tests of FRP-to-timber joints strengthened with externally bonded FRP plates.