Flexural behaviour of glulam beams from novel sandwich panels

Abstract

This paper presents the flexural behavior of full-scale glue-laminated (glulam) beams made by gluing layers of fibre composite sandwich panels together. Sandwich beams with flatwise, edgewise, and combined sandwich laminations were investigated to determine the most effective use of composite sandwich construction for structural beam applications. The building block of this innovative beam is a novel composite sandwich structure made up of glass fibre reinforced polymer skins and high strength phenolic core material. Four-point static bending test was conducted to evaluate the stiffness and strength of the full-scale glulam sandwich beams. The effects of wrapping the glulam sandwich beams with one-layer of tri-axial glass fibres on the flexural behaviour were also examined. The results of the experimental investigation indicated that the glulam sandwich beams with edgewise laminations is the most efficient section in terms of strength and stiffness among the different beam configurations. This beam failed with a 20% higher bending strength and has a 4% higher bending stiffness than beams with flatwise and combined sandwich laminations. The glulam sandwich beams with fibre wraps behaved slightly stiffer and failed a higher load compared to the beams without wraps. In general, all the beams presented bending stiffness and strength comparable with structural timber showing that the glulam sandwich beam is a viable alternative to hardwood timber.