Effect of repairing flexural damaged beams with high strength mortar and CFRP on strength

During an earthquake, ground motions generate bending moments on beams. These moments, especially occurring in the middle of the beams, cause stress differences on the top and bottom surfaces, leading to cracks and fractures. The strengthening of damaged structural elements, a critical issue in civil engineering, enhances the safety and durability of structures. This study aims to investigate the effects of high-strength mortar and CFRP (Carbon Fiber Reinforced Polymer) on the repair and strengthening of beams that have sustained flexural damage. As part of the experimental work, a total of 8 beam specimens with cross-sectional dimensions of 250 mm×400 mm and a length of 2000 mm were produced. The beams were subjected to bending tests where loads were applied at four points on the beams, observing their maximum load-carrying capacity and resulting deformations. For additional damage, a rectangular void measuring 100 mm×700 mm was created in the middle span of 4 damaged beams. Subsequently, these beams were repaired using high-strength mortar and CFRP fabric with various detailing techniques. The repaired 6 beam specimens were retested under bending, with loads applied at four points to determine their maximum load-carrying capacities. The experimental results were used to analyze the effects of the repair methods on the load-carrying capacity of the beams. Based on the findings, the potential of high-strength mortar and CFRP to enhance the strength of damaged beams was evaluated. The load-carrying capacity, stiffness, ductility, and energy dissipation capacity of each specimen were calculated. All results were compared to assess the effectiveness of the repair methods in restoring the beams.