Behavior and Strength of Concrete Slab Reinforced by GFRP Bar and Strengthened by Pre-Stressed Laminated CFRP under Uniformly Distributed Loading

International Journal of Civil Engineering

© 2025 by SSRG - IJCE Journal

Volume 12 Issue 11

Year of Publication : 2025

Authors : Alabid Ali Abdul Naby Ahmed, Leong Sing Wong, Mutaz Kadhim Medhlom

10.14445/23488352/IJCE-V12I11P110

How to Cite?

Alabid Ali Abdul Naby Ahmed, Leong Sing Wong, Mutaz Kadhim Medhlom, "Behavior and Strength of Concrete Slab Reinforced by GFRP Bar and Strengthened by Pre-Stressed Laminated CFRP under Uniformly Distributed Loading," SSRG International Journal of Civil Engineering, vol. 12,  no. 11, pp. 121-131, 2025. Crossref, https://doi.org/10.14445/23488352/IJCE-V12I11P110

Abstract:

A Total of six specimens, including a control without strengthening, were tested under the effect of pressure load that represented a solid concrete slab reinforced by Glass Fiber Reinforced Polymer (GFRP) bars with four edges fixed as boundary conditions and strengthened by different layouts of Carbon Fiber Reinforced Polymer (CFRP) strips laminated. The behavior and strength of the tested specimens were discussed and evaluated, including strength and deformation, stiffness, ductility, and energy dissipation, based on the recorded and observed results of each specimen. As a result, the presence of CFRP strips or laminated CFRP gave an increase in load strength capacity due to representing an additional reinforcement that was placed at the tension zone of tested specimens, which led to an increase in resistance against applied loadings and a decrease in deflection. The failure mode occurs as flexural due to the design requirements of a reinforced concrete slab by applying the methodology proposed by ACI-318-2019, as under reinforcement due to the yielding in reinforcement before concrete failure. The design principle of GFRP bars without traditional reinforcements is based on the equivalent tension force (differing in yielding strength).

Keywords:

Reinforced concrete slab, Pre-stressed, Strengthening, CFRP strips, Laminated CFRP, Flexural failure, Concrete enhancement strength.

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