Experimental and Numerical Study of Flexural Strength of Kenaf Fibre-Reinforced Concrete Beams

The increasing need for eco-friendly building materials has led to research into using natural fibres as reinforcement in concrete structures. This study investigates the flexural strength of kenaf fibre-reinforced concrete (KFRC) beams using both experimental and numerical analysis. Kenaf fibres are known for their excellent tensile strength and environmental friendliness. Four beam samples (A, B, C, and D) were tested. The samples had 100mm (control), 125 mm, 150 mm, and 175 mm shear spacing, respectively. Kenaf fibre was added to samples B, C, and D to determine its effect on flexural performance at an optimal content and length. The three-point bending test was conducted to evaluate key parameters such as flexural strength and deflection. Additionally, the imaging characterisation of kenaf fibre reinforced concrete and plain concrete using micro-and nanoparticles was examined and analysed using scanning electron microscopy. A finite element model was developed using Abaqus software to simulate the flexural behaviour of KFRC beams and validate the experimental results. The beam Samples A, B, C, and D have the flexural strength of 62 MPa, 72 MPa, 68 MPa, and 55 MPa, respectively and deflection values of 23.08 mm, 19.03 mm, 21.85 mm, and 31.25 mm, respectively. When comparing the flexural strength of samples B and C to that of the control sample, the results showed that the flexural strength rose by 10% and 4.6%, respectively. The flexural strength and deflection numerical models are 94% and 90%, respectively. The efficiency of the suggested model was confirmed by the numerical simulations, which demonstrated good agreement with experimental results. The potential of kenaf fibre as a workable substitute for shear reinforcement in environmentally friendly concrete constructions is highlighted by this study.