Experimental trends of FRP-to-timber joint tests

Research on the application of externally bonded fibre-reinforced polymer (FRP) composites for the strengthening and repair of timber structures is limited. Of central importance to the success of strengthening timber with FRP is an adequate understanding of the influence of key geometric and material properties on the physical behaviour of FRP-to-timber bonded interfaces. In addition, a lack of bond strength models hindering widespread applications of FRP to timber. This paper reports experimental trends observed in over 180 tests on FRP-to-timber joints conducted at The University of Hong Kong as part of a doctoral program of study by the first author of this paper. A single-shear joint test configuration was utilised to experimentally investigate the strength and behaviour of FRP-to-timber bonded interfaces. Test variables reported herein include (i) bonded plate length, (ii) adhesive type, (iii) FRP type, (iv) timber species, and (v) adhesive thickness. These variables are fundamental and can lead to behavioural understandings as well as the development of design equations.