Published October 30, 2025 | Version v1
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Structural Assessment of Reinforced Concrete Beams Strengthened with CFRP Laminates

Description

Carbon Fiber Reinforced Polymer (CFRP) laminates have become a widely accepted solution for strengthening and retrofitting reinforced concrete (RC) beams due to their high tensile strength, corrosion resistance, and ease of installation. This study presents an experimental evaluation of RC beams strengthened externally with CFRP laminates using epoxy bonding. A total of eight beams were cast and tested under two-point loading, including control beams and beams strengthened with different CFRP configurations such as single-layer, double-layer, and U-wrap anchorage. Structural parameters including load-carrying capacity, mid-span deflection, cracking pattern, stiffness, and failure modes were systematically analyzed. The results show that CFRP strengthening significantly enhances flexural capacity, delays crack initiation, and improves overall stiffness. The double-layer CFRP configuration exhibited up to 42% higher load-carrying capacity compared to the control beam, while U-wrap anchorage minimized premature debonding. The study confirms that CFRP laminates offer an efficient and practical strengthening method for extending the service life of RC structures.

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Dates

Issued
2025-10-30
Carbon Fiber Reinforced Polymer (CFRP) laminates have become a widely accepted solution for strengthening and retrofitting reinforced concrete (RC) beams due to their high tensile strength, corrosion resistance, and ease of installation. This study presents an experimental evaluation of RC beams strengthened externally with CFRP laminates using epoxy bonding. A total of eight beams were cast and tested under two-point loading, including control beams and beams strengthened with different CFRP configurations such as single-layer, double-layer, and U-wrap anchorage. Structural parameters including load-carrying capacity, mid-span deflection, cracking pattern, stiffness, and failure modes were systematically analyzed. The results show that CFRP strengthening significantly enhances flexural capacity, delays crack initiation, and improves overall stiffness. The double-layer CFRP configuration exhibited up to 42% higher load-carrying capacity compared to the control beam, while U-wrap anchorage minimized premature debonding. The study confirms that CFRP laminates offer an efficient and practical strengthening method for extending the service life of RC structures.

References

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