Bond Strengthening of Unbonded RC Beams with the Advanced Carbon Fiber Reinforcement Polymer (CFRP) Composites

International Journal of Civil Engineering

© 2022 by SSRG - IJCE Journal

Volume 9 Issue 2

Year of Publication : 2022

Authors : Fares Jnaid

10.14445/23488352/IJCE-V9I2P103

How to Cite?

Fares Jnaid, "Bond Strengthening of Unbonded RC Beams with the Advanced Carbon Fiber Reinforcement Polymer (CFRP) Composites," SSRG International Journal of Civil Engineering, vol. 9,  no. 2, pp. 21-43, 2022. Crossref, https://doi.org/10.14445/23488352/IJCE-V9I2P103

Abstract:

Confinement of concrete increases the bond between steel rebars and the surrounding concrete. This paper studies the effects of Carbon Fiber Reinforcement Polymer CFRP confinement in increasing the bond strength of concrete beams with unbonded reinforcement. The author developed a Finite Element (FE) model and verified it against the experimental data. In addition, the author developed an innovative numerical, analytical procedure to compute the strength of concrete beams with unbonded reinforcement and strengthened with CFRP sheets. The author subjected the beams to unbonded lengths that varied from 0 to full span and observed the mode of failure. Beams that failed in bond were wrapped with CFRP sheets in order to increase the bond between steel reinforcement and the surrounding concrete. This research concluded that wrapping beams with CFRP sheets restored up to 93% of ultimate capacity and increased the mid–deflection by up to 73%. In some cases, CFRP sheets were able to switch the mode of failure from an undesirable bond failure to a more attractive flexural failure.

Keywords:

Concrete, Beams, CFRP, Bond, Strengthening.

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