Carbon Fiber in Structural Reinforcement and Retrofitting
Birendra Kumar Deepak, Chitranjan Kumar, Praveen Verma, Mayank Chauhan, Abhishek Rana
Department of Civil Engineering, Sri Venkateshwara University, Gajraula (UP), 244236
Abstract - The rapid deterioration of civil infrastructure, compounded by seismic vulnerability and environmental exposure, necessitates advanced retrofitting techniques to ensure long-term safety and serviceability. Conventional methods such as steel jacketing and concrete encasement are often limited by increased dead load, corrosion susceptibility, and labor intensity. In this context, carbon fiber reinforced polymer (CFRP) composites have emerged as a highly effective alternative owing to their superior tensile strength, low density, corrosion resistance, and ease of application. This dissertation presents a comprehensive review and synthesis of the application of CFRP in the structural retrofitting of reinforced concrete (RC) and steel members. The fundamental properties, manufacturing processes, and performance characteristics of carbon fibers are first discussed to establish the material context. Subsequently, experimental and analytical investigations on CFRP retrofitting of beam–column joints, RC columns, and entire RC frames are critically examined, with particular emphasis on seismic performance, hysteresis behavior, and energy dissipation. In addition, the role of CFRP in strengthening steel structures is analyzed, including bond behavior, fatigue resistance, and failure modes. The advantages of CFRP, such as high strength-to-weight ratio and durability, are weighed against limitations including debonding, anchorage challenges, and cost considerations. Recent advances in hybrid retrofitting strategies and smart health monitoring of CFRP retrofits are also highlighted. The review underscores that CFRP-based retrofitting significantly enhances load-bearing capacity, ductility, and seismic resilience of structural systems, positioning CFRP as a sustainable and innovative solution for extending the service life of aging infrastructure. Future research directions include cost optimization, large-scale field applications, and integration with digital monitoring technologies for real-time performance assessment.
Key Words: CFRP, Retrofitting, Carbon Fiber, Reinforcement, Carbon Fiber Retrofitting
