The Behavior of RC Beams Retrofitted with Carbon Fiber Reinforced Polymers (CFRP)
Received: 17 March 2022 | Revised: 5 April 2022 | Accepted: 7 April 2022 | Online: 30 April 2022
The need for the introduction of economical and quicker retrofitting techniques is increasing due to the ever-aging infrastructure and damages produced by major catastrophic events around the world. The application of Carbon Fiber Reinforced Polymers (CFRP) for strengthening and retrofitting of reinforced concrete structures is gaining popularity due to its higher strength, lightweight, durability, corrosion resistance, and aesthetic value. This study presents the results of two strengthened and two retrofitted beams in comparison to control specimens. Two specimens were strengthened and two were retrofitted by attaching CFRP (Sika Carbo-Dur S812 or Sika-Wrap 230C) to the tension side of the beams using high strength epoxy. The results show that one CFRP strip/wrap simply attached at the tension side can help the damaged beam regain/pass the original strength. All specimens fail due to debonding of CFRP from the concrete surface emphasizing the need for efficient anchorage systems. Among the four patterns adopted, CFRP strips along with u-shaped anchorages at the ends provided the highest strength enhancement of 17.36%.
Keywords:CFRP, strengthening, retrofitting, reinforced concrete beams, debonding
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