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Journals / Gazi University Journal of Science / 2026 / Volume: 38 Issue: 2

An Experimental Investigation of CFRP Strengthening Efficiency on The Retrofitted Damaged Geopolymer Concrete Beams

Güray Arslan(YILDIZ TEKNİK ÜNİVERSİTESİ)0000-0001-5004-8617
Mehdi Öztürk(İSTANBUL AREL ÜNİVERSİTESİ)0000-0003-4147-0431
Kadir Şengün(İSTANBUL AYDIN ÜNİVERSİTESİ)0000-0002-4893-0093
Pages
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Publication Date
2025-06-01
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

The deflection capability of the retrofitted beams in the tested series was between 18% -80% lower than the reference beams.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:In this study, beams produced by geopolymer concrete (GC) with different properties such as compressive strengths, stirrups ratios, and shear-span to effective depth ratio (a/d) were tested up to the failure to attain the load-deflection behaviors.
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Key Findings & Data:According to this study, applying the CFRP strengthening to damaged GC beams increased the load-carrying capacity between 4% - 72%, depending on the compressive strength, stirrups spacing, and a/d with reference to the reference GC beams.
💡
Conclusion & Impact:The deflection capability of the retrofitted beams in the tested series was between 18% -80% lower than the reference beams.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Retrofitted beam · Strengthening · CFRP

Abstract

In this study, beams produced by geopolymer concrete (GC) with different properties such as compressive strengths, stirrups ratios, and shear-span to effective depth ratio (a/d) were tested up to the failure to attain the load-deflection behaviors. Then, tested damaged beams were retrofitted using Carbon Fiber Reinforced Polymer (CFRP) in both shear and flexure to examine the CFRP strengthening efficiency. A three-point flexural test was conducted on both reference and retrofitted GC beams. According to this study, applying the CFRP strengthening to damaged GC beams increased the load-carrying capacity between 4% - 72%, depending on the compressive strength, stirrups spacing, and a/d with reference to the reference GC beams. The area calculated under the load-deflection graph of the retrofitted GC beams was lower than the reference beams in all tested series. The initial stiffness in the tested retrofitted beams was generally obtained lower compared to the reference GC beams. The deflection capability of the retrofitted beams in the tested series was between 18% -80% lower than the reference beams.

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Cite This Article

Arslan, G., Öztürk, M., Şengün, K. (2025). An Experimental Investigation of CFRP Strengthening Efficiency on The Retrofitted Damaged Geopolymer Concrete Beams. Gazi University Journal of Science, Volume: 38 Issue: 2. https://doi.org/10.35378/gujs.1582884

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