Comparative Experimental Study of Eco-Composite Reinforced Concrete Beams Under Flexural Loading: Sustainability Factors vs. Mechanical Performance

This study is an experimental study on flexural strengthening of reinforced concrete beam where three types of epoxy-bonded jacketing systems are used (glass fiber-reinforced composite (GFRC, S1), jute fiber-reinforced composite (JFRC, S2), and hybrid fiber-reinforced composite (HFRC, S3)) and an unjacketed control beam (S0). All the specimens were subjected to displacement-controlled three-point bending to measure the enhancement of strength, stiffness, and energy absorption using mass-normalized (TPM) and synthetic-content-normalized (TSM) performance indices. Jacketing compared to control also raised the maximum load from 11.80 N to 17.10 N for GFRC (+44.9%), to 14.64 N for JFRC (+24.1%), and to 14.89 N of HFRC (+26.2%). The energy taken up rose from 38.44 J (S0), 152.50 J (S1, +297%), 95.32 J (S2, +148%), and 132.79 J (S3, +245%). Flexural strength was also increased to 56.26 MPa (S1), 43.54 MPa (S2), and 51.38 MPa (S3) and yield strength was raised from 10.43 MPa (S0) to 26.40 MPa (S1), 16.84 Mpa (S2), and 23.05 Mpa (S3). The increase of flexural modulus between S0 (4871.33 MPa) and S1 (12,322.34 MPa), S2 (7862.61 MPa), and S3 (10,759.57 MPa) showed the enhancement of the stiffness. Mass-normalized performance showed great overall efficiency in the case of GFRC and HFRC, with TPM = 3.70 and 3.60 J/kg, respectively, and synthetic-content efficiency was higher in the case of JFRC, with TSM = 9.66 J/kg, which is the advantage of low-synthetic reinforcement in energy-based performance. In general, the suggested jacketing systems have a great influence on flexural responsiveness and power absorption, whereby GFRC and JFRC offer maximum capacity and stiffness, respectively, and the greatest efficiency per unit synthetic material, respectively. In terms of novelty, the paper is one of the first to measure the sustainability-based performance of an epoxy-bonded GFRC, HFRC, and bio-based JFRC jacketing, comparing the results in terms of synthetic-content efficiency (TSM) and mass-normalized indices, which reflect the energy absorption benefits per unit of synthetic material.