Investigation on the mechanical behaviour of hybrid fibre reinforced polymer composite beam

Fibre reinforced polymer (FRP) composites have been proven a viable alternative to conventional construction materials such as timber, steel, and reinforced concrete due to its high strength-to-weight, light weight, durable, and corrosion resistant properties. Several studies suggested the effective use of FRP composites in sandwich structures. This paper presents the physical and mechanical properties of a sandwich-structured glue-laminated beam, named as hybrid FRP composite beam, developed by CarbonLOC Pty Ltd in cooperation with the Centre of Excellence in Engineered Fibre Composites (CEEFC) in University of Southern Queensland (USQ). This beam combines the strength and stiffness of glue-laminated panels oriented in the edgewise position bonded with the high tensile strength and modulus Glass Fibre Reinforced Polymer (GFRP) skin plates at the top and bottom. The average experimental failure loads of the beam in flexure, shear, longitudinal compression, and tangential compression are 53.45 kN, 211.73 kN, 450.06 kN, and 220.31 kN, respectively, which corresponds to strength of 106.90 MPa, 35.29 MPa, 75.01 MPa, and 61.20 MPa, respectively. The effective stiffness of the beam was enhanced due to top and bottom GFRP plates. Theoretical prediction showed reasonably comparable failure load with the experimental results.