Analytical and experimental evaluation of deflection behaviour in CFRP-reinforced high-strength concrete beams

High-strength concrete (HSC) beams reinforced with fiber-reinforced polymer (FRP) bars typically exhibit a greater deflection than steel bars. A new equation for predicting the maximum deflection and effective moment of inertia is proposed in the current study in a form like that found in the literature and the ACI-Code. The experimental results of the load-deflection curves of twenty-seven carbon fiber-reinforced polymers (CFRP)-reinforced high-strength concrete beams are used to derive the proposed equation. Chopped carbon fiber (of 0, 0.25, and 0.5%) and silica fume were used to create the high-strength concrete mixtures. A total of twenty-seven distinct mixes were prepared, each intended for the casting of one beam with 100×150×2250mm dimensions. The CFRP was utilized to reinforce the beams by 1Ø5mm, 2Ø5mm, 3Ø5mm, and 4Ø5mm. The beams were tested with four-point loading to determine the flexural strength. Characteristics such as compressive strength, modulus of elasticity, reinforcement ratio (ρ/ρb), and percentage of chopped carbon fiber (CCF%) were considered to develop the models. The findings demonstrate that the effective moment of inertia and deflections predicted by the proposed equation closely match the experimental values. A high agreement was also discovered between the results and the deflection capacities predicted by the analytical model.