Evaluating mechanical efficiency of glass fibres in a polymer profile

Abstract

This study focuses on the mechanical performance of pultruded glass fibre-reinforced polymer (GFRP) profiles developed for structural applications. Fibre content determines the tensile resistance of such components, and technical specifications describe this essential parameter. However, it does not determine the actual reinforcement efficiency. This manuscript illustrates the above inference both experimentally and analytically, investigating a GFRP square hollow section (SHS) profile available at the market. Standard tensile coupon test defines the material characteristics; a three-point-bending test determines the mechanical performance of the profile. A digital image correlation system captures deformations and failure mechanism of the SHS bending specimen. The developed finite element model with smeared reinforcement estimates the efficiency of the glass filaments, i.e. the ability to predict the actual mechanical resistance (flexural stiffness) under the assumption of the experimentally determined elasticity modulus of bare fibres. Scanning electron microscopy relates the composite microstructure and mechanical performance of the selected profile.