Shear Strength and Behavior of Reinforced Concrete Corbels Containing either Carbon Fibers or Stirrups

Sanaa Ismael Khaleel, Bayan Anwer Ali, Zrar Sedeeq Othman


In the present paper, an experimental research is presented regarding the shear strength and behavior of concrete corbels with carbon fiber or stirrups as shear reinforcement. Tests were carried out on ten120 x 250 x 250 mm corbels subjected to vertical loading. The influence of concrete grade type (normal and moderately high strength concretes), carbon fiber percentage and of the percentage of the horizontal shear reinforcement on the shear strength of the corbels were considered. The test results in term of load-deflection curves and crack patterns show that the shear strength and deformation capacity was improved with the increase in the percentage of carbon fibers in reinforced concrete corbels. These clearly demonstrate the benefits of using carbon fiber as shear reinforcement in combination (fibers and stirrups) or as replacement for stirrups. An equation was proposed for predicting the shear strength of the reinforced concrete corbels subjected to vertical load. The equation was compared with equations given by ACI 318-14. The ACI equations were more conservative for predicting the ultimate shear strength of all corbels.

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