Abstract

The bending and shear behavior of RC beams strengthened with Carbon Fiber-Reinforced Polymers (CFRP) is the primary objective of this paper, which is focused on the failure mechanisms and on the moment-curvature response prior-to, and post, strengthening with different amounts and layouts of the CFRP reinforcement. Seven reinforced concrete beams were tested in 4-point bending, one without any CFRP reinforcement (control beam, Specimen C1), four with the same amount of CFRP in flexure but with different layouts of the reinforcement for shear (Specimens B1–B4), and two with extra reinforcement in bending, with and without reinforcement in shear (Specimens B6 and B5, respectively). During each test, the load and the mid-span deflection were monitored, as well as the crack pattern. The experimental results indicate that: (a) increasing the CFRP reinforcement above certain levels does not necessarily increase the bearing capacity; (b) the structural performance can be optimized through an appropriate combination of CFRP flexural and shear reinforcement; and (c) bond properties at the concrete–CFRP interface play a vital role, as the failure is very often triggered by the debonding of the CFRP strips. The experimental values were also verified analytically and a close agreement between the analytical and experimental values was achieved.

Highlights

  • The Kingdom of Saudi Arabia, as well as rest of the world, contains a wide range of reinforced concrete infrastructure which ranges from small residential houses to multi-story buildings, towers, and pre-stressed concrete bridges

  • This behavior of low ductility in reinforced concrete structures retrofitted with Carbon Fiber-Reinforced Polymers (CFRP) is not desirable, as it does not provide any kind of early warning before failure, resulting in the sudden collapse of the structure

  • The current study evaluated the effect of the CFRP reinforcement ratio on failure patterns of reinforced concrete beams

Read more

Summary

Introduction

The Kingdom of Saudi Arabia, as well as rest of the world, contains a wide range of reinforced concrete infrastructure which ranges from small residential houses to multi-story buildings, towers, and pre-stressed concrete bridges. CFRP has been widely used for the purpose of strengthening reinforced concrete, masonry, and steel infrastructure. By adopting the correct retrofitting technique, CFRP can significantly increase the shear and flexure strength of concrete structures as compared to the normal concrete structure. Shear, and compression cracks can be prevented in reinforced concrete beams with the help of CFRP application. Once the failure strain is reached, CFRP shows no signs of warning, breaks suddenly, and results in the loss of its strength. This behavior of low ductility in reinforced concrete structures retrofitted with CFRP is not desirable, as it does not provide any kind of early warning before failure, resulting in the sudden collapse of the structure

Literature Review
Experimental Plan and Setup
No Control-C1
Results and Discussions
Moment-curvaturerelation relation for
Analytical Prediction of Beam Capacities
Control Specimen C-1
Beam CFRP B1
10. In the case of 11 shows theoffailure patterns beam CFRP
12. In the case of beam
Beam CFRP B6
Beam CFRP B4
Beam CFRP B5
Beam CFRP
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call