Flexural Performance Evaluation Of Glass Fiber Reinforced Polymer Bars (GFRP) In Doubly Reinforced Beams: An Experimental Approach

Abstract

using the primary goal of evaluating their efficacy as a sustainable substitute for conventional steel reinforcement, this experimental study investigates the flexural performance of double-reinforced concrete beams strengthened using Glass Fibre fiber-reinforced polymer (GFRP) bars.  Recent years have seen a significant increase in interest in the use of GFRP bars in concrete buildings due to their inherent benefits, which include increased durability, reduced material weight, and corrosion resistance.  Five examples were manufactured for this investigation; two included only GFRP bars, two included hybrid bars, and one had only steel bar beams for comparison.  The beams are full-scale, with dimensions of 152 and 230 mm in cross-section and 3000 mm in length.  With a factored load of 2.5 kips/ft, the beam specimens were constructed as standard doubly reinforced beam designs, with 5#4 bars in tension and 2#4 bars in compression.  T-Rod International produced the GFRP bars utilized in this investigation.  To assess their flexural behavior, including load-deflection response, cracking patterns, and ultimate load capacity, beam specimens were put through three-point bending tests.  The efficiency of GFRP bars in doubly reinforced beams in comparison to traditional steel reinforcement is assessed through the analysis of experimental data.  Deflection, ultimate strength, and failure mechanisms are the main provisions being examined.  GFRP bars exhibit brittle behavior and a 54% greater tensile strength than steel bars. Steel-reinforced beams have a 30% greater ultimate load capacity than pure GFRP-reinforced beams, whereas hybrid GFRP-reinforced beams have an 18% lower ultimate load capacity.  In GFRP and hybrid samples, the maximum mid-span deflection caused by the ultimate load is significantly greater than in steel samples.