Structural Engineering and Mechanics

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Effects of a new stirrup hook on the behavior of reinforced concrete beams

  • Zehra Sule Garip (Department of Civil Engineering, Karabuk Universityy) ;
  • Furkan Erdema (Department of Civil Engineering, Karabuk Universityy)
  • Received : 2023.10.10
  • Accepted : 2024.07.15
  • Published : 2024.08.10
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Abstract

The primary aim of this study is to introduce an innovative configuration for stirrup hooks in reinforced concrete beams and analyze the impact of factors such as stirrup spacing, placement, and hook lengths on the structural performance of reinforced concrete beam elements. A total of 18 specimens were produced and subjected to reversed cyclic loading, with two specimens serving as reference specimens and the remaining 16 specimens utilizing a specifically developed stirrup hook configuration. The experiment used reinforced concrete beams scaled down to half their original size. These beams were built with a shear span-to-depth ratio of 3 (a/d=3). The experimental samples were divided into two distinct groups. The first group comprises nine test specimens that consider the contribution of concrete to shear strength, while the second group consists of nine test specimens that do not consider this contribution. The preparation of reference beam specimens for both groups involved the utilization of standard hooks. The stirrup hooks in the test specimens are configured with a 90-degree angle positioned at the midpoint of the bottom section of the beam. The criteria considered in this study included the distance between hooks, hook angle, stirrup spacing, hook orientation, and hook length. In the experimental group examining the contribution of concrete on shear strength, it was noted that the stirrup hooks of both the R1 reference specimen and specific test specimens displayed indications of opening. However, when the contribution of concrete on shear strength was not considered, it was observed that none of the stirrup hooks proposed in the R0 reference specimen and test specimens showed any indications of opening. Neglecting the contribution of concrete in the assessment of shear strength yielded more favorable outcomes regarding structural robustness. The study found that the strength values obtained using the suggested alternative stirrup hook were similar to those of the reference specimens. Furthermore, all the test specimens successfully achieved the desired strengths.

Keywords

Acknowledgement

This article is a part of Furkan ERDEM's M.Sc. thesis titled "Investigation of A New Stirrup Hook of Behavior in Reinforced Concrete Beams" under the supervisor of Assistant Professor Dr. Zehra Sule GARIP.

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