Numerical parametric study on the flexural response and failure characteristics of GFRP-concrete composite beams with GFRP dowel shear connectors

Abstract

This paper presents the findings of a numerical study conducted to examine the influence of different structural parameters on the response of a complete steel-free, glass fiber reinforced polymer (GFRP) dowel connector based, GFRP-concrete composite beam. The three-dimensional nonlinear analysis was carried out using the commercial software package Abaqus/CAE, and the damage evolution in concrete was defined using the concrete damaged plasticity (CDP) material model. The methodology was validated by comparing the results against those of an experimental study. The results showed that the composite beam ultimately fails either due to the shearing of the web or the rupture of the connected GFRP flange around the connection points; and its load-carrying capacity and stiffness have a proportional relationship with the compressive strength of concrete, the longitudinal elastic modulus of the profile, the elastic modulus of the connectors, the width of the concrete slab, the depth of the composite section, and the wall thickness of the profile; and an inverse relationship with the span length and the angle of inclination of connectors. The vertical deformations are significantly affected by the shear modulus of the GFRP profile; a relatively better response is obtained with a closed section profile; an optimum connector diameter and longitudinal spacing value exists at which the load carrying capacity is maximum; and the provision of web cutouts deteriorates the overall structural behavior. The critical findings of the study will assist the structural designers/researchers in developing an efficient and optimum design configuration for such structures in the near future.