Impact of wrap quantity on strength of damaged and undamaged CFRP-reinforced structural members

In this study, the effect of carbon fiber reinforced polymer (CFRP) wrapping on the compressive and bending behavior of damaged reinforced concrete structural elements located in high earthquake risk areas was investigated in detail. The main objective was to evaluate the potential of CFRP wraps as an effective strengthening technique for improving the mechanical performance of concrete members that have already sustained damage. During the experimental phase, concrete specimens in the form of 15×15×15 cm cubes and 10×10×50 cm prisms were prepared using CEM IV 32.5 pozzolanic cement, which is commonly used in structural applications due to its durability and environmental benefits. After subjecting these specimens to controlled damage to simulate real-life structural degradation, they were reinforced using single and double layers of CFRP wrapping. The mechanical performances of these wrapped specimens were then assessed through compressive and bending strength tests. The results demonstrated that CFRP wrapping significantly enhanced the compressive strength of the specimens, with double-layer applications showing the greatest improvements. However, the effect on flexural strength was found to be more limited, indicating that although CFRP is 60.83% effective in resisting compressive loads, its contribution to flexural capacity may require additional considerations. Furthermore, double-layer CFRP wrapping not only improved strength but also increased deformation capacity, indicating enhanced ductility and energy absorption. Despite the relatively high cost of CFRP materials, these findings highlight the technique as a practical and efficient solution for the rehabilitation and strengthening of compression load-bearing members, particularly in regions vulnerable to seismic activity.