Mechanical performance analysis in bending of glulam beams reinforced with synthetic Vectran fibres

Abstract

Synthetic fibres applied as reinforcement in glued laminated timber (glulam) intend to increase the mechanical performance of beams, changing the brittle to ductile mechanical behaviour of wooden beams. This paper investigates the experimental results of glulam beams reinforced with synthetic fibre subjected to bending and compares them with those obtained by both an analytical method and the numerical method using the Ansys^® software. Glulam beams were produced with a low-grade strength class wood species (Pinus elliottii) glued with an adhesive of emulsion isocyanate polymeric and reinforced with Vectran^® synthetic fibres, positioned on the bottom of the beam. This type of fibre is not yet widely used for structural reinforcement. A three-point bending test was performed for loading in the elastic regime of the glulam beams. The results obtained indicate acceptable approximations of vertical displacements and normal stresses due to the bending of the beam with eight layers of synthetic fabric, both favourable to structural safety, in addition to the significant increase in stiffness of glulam with the introduction of Vectran^® fibre reinforcement.