Experimental and Numerical Analysis of CFRP-Strengthened Reinforced Concrete Beams at Various Temperatures

Öz

This study investigates the effects of various temperatures on the performance of reinforced concrete (RC) beams strengthened with carbon fiber reinforced polymer (CFRP) using both experimental and numerical methods. A total of 24 beam specimens with dimensions of 10×15×60 cm were cast using C25/30 concrete. Half of the specimens were strengthened by CFRP wrapping, while the remaining half served as the control group. A total of 24 specimens were divided into three groups: 8 specimens were tested at 24 °C (room temperature), 8 specimens at 120 °C, and 8 specimens at 240 °C after being exposed to these temperatures for two hours. The experimental results showed that CFRP strengthening provided approximately 15% higher flexural strength at room temperature. In addition, while no significant strength loss was observed up to 120 °C, an approximate 8% reduction in strength occurred at 240 °C due to the adverse effect on the CFRP layer. The findings were further validated through finite element analyses conducted using Ansys Workbench. Numerical results were largely consistent with the experimental data, confirming that CFRP strengthening maintains its effectiveness up to elevated temperatures. At the same time, performance degradation becomes evident once the critical temperature threshold is exceeded. Overall, the results highlight that CFRP strengthening offers significant advantages in terms of post-fire performance, although its efficiency is clearly limited under high-temperature exposure.

Anahtar Kelimeler

• Carbon fiber reinforced polymer
• Strengthening
• High temperature
• Flexural strength
• Reinforced concrete beam

Kaynakça

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