ABSTRACT
Due to the different properties of GFRP bars, the available finite element packages for modelling shear critical GFRP reinforced members are questionable. This paper presents a three-dimensional (3D) nonlinear finite element analysis (FEA) model for shear critical glass fibre-reinforced polymer (GFRP) reinforced concrete beams. The beams were reinforced in longitudinal direction and there was no shear reinforcement. The FEA were carried out using concrete damage plasticity model in ABAQUS along with suitable constitutive model for concrete. Perfect bond was assumed between concrete and GFRP reinforcement. A generalized bi-linear tension stiffening model, based on the strain energy density, was used to model the contact between the concrete and GFRP bars. The FEA results were compared with the test results of GFRP reinforced beams. The robustness of the model was investigated for three different parameters: depth of beam, shear span to depth ratio, and concrete strength. The results obtained from FE analysis were analyzed for its load-deflection behaviour, crack patterns, ultimate loads; and the FE results were also compared with the test results. The comparison reveals that the model predicts the behaviour of shear critical GFRP reinforced concrete beams with reasonable degree of accuracy.
Abbreviation: Glass Fibre Reinforced Polymer (GFRP)
Acknowledgments
The authors would like to acknowledge that no funding was received from public, commercial, or not-for-profit sectors for this research.
Notations
The symbols that are used in this paper are as follows:
= | = shear span | |
b | = | = width of beam |
h | = | = depth of beam |
= | = effective depth of beam | |
= | = shear span to depth ratio | |
k | = | = stress decay factor |
n | = | = curve fitting factor |
ρf | = | = reinforcement ratio =Af/bd |
ρb | = | = balanced reinforcement ratio = |
fc | = | = compressive stress of concrete |
ft | = | = tensile stress of concrete |
fc’ | = | = compressive strength of concrete |
ft’ | = | = tensile strength of concrete |
fu | = | = tensile strength of GFRP |
= | = effective cohesion stress | |
= | = area of reinforcement | |
Ef | = | = modulus of elasticity of GFRP |
= | = span length of beam | |
P | = | = Applied load |
V | = | = shear strength |
= | = experimental shear strength | |
VFEA | = | = predicted shear strength |
β1 | = | = stress block factor |
εt | = | = tensile strain |
= | = concrete strain at | |
εc | = | = compressive strain |
εcr | = | = strain at peak tensile stress (cracking strain) |
εu | = | = ultimate strain of GFRP |
εpl | = | = plastic strain |
eel | = | = elastic strain |
etotal | = | = total strain |
δexp | = | = deflection measured from experiment |
δFEA | = | = deflection measured from FEA |
Disclosure statement
No potential conflict of interest was reported by the authors.
Additional information
Notes on contributors
Md Shah Alam
Md Shah Alam received his Ph. D. in Civil Engineering from Memorial University of Newfoundland, Canada; M. Eng. and B. Sc. in Civil Engineering from Saitama University, Japan and Bangladesh University of Engineering and Technology, respectively. He is working as a Faculty member in Civil Engineering Department of University of Bahrain. His research interest includes reinforced concrete, finite element analysis, use of advanced composite materials, strengthening and rehabilitation of structures, and structural health monitoring.
Amgad Hussein
Amgad Hussein is an Associate Professor and Head of the Department of Civil Engineering at Memorial University of Newfoundland. He obtained his B. Sc. in Civil Engineering from Ain-Shams University in Cairo, Egypt, and his M. Eng. and Ph. D. in Civil Engineering from Memorial University of Newfoundland, Canada. His research interest includes advanced composite materials, shear in reinforced concrete beams and slabs, serviceability and finite element analysis of concrete structures. He is a Fellow of the Canadian Society for Civil Engineering.