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Strengthening of reinforced concrete beams using external steel members

  • Demir, Ali (Manisa Celal Bayar University, Department of Civil Engineering) ;
  • Ercan, Emre (Ege University, Department of Civil Engineering) ;
  • Demir, Duygu Donmez (Manisa Celal Bayar University, Department of Mathematics)
  • Received : 2017.10.23
  • Accepted : 2018.03.22
  • Published : 2018.05.25

Abstract

The objective of this study is to devise an alternative strengthening method to the ones available in the literature. So, external steel members were used to enhance both flexural and shear capacities of reinforced concrete (RC) beams having insufficient shear capacity. Two types of RC beams, one without stirrups and one with lacking stirrups, were prepared in the study. These beams were strengthened with external steel clamps devised by the authors and with external longitudinal reinforcements. Although the use of clamps alone didn't have a significant effect on the load carrying capacity of the tested beams, the ductility increased approximately tenfold and the failure behavior changed from brittle to ductile. Although the use of clamps and longitudinal reinforcements together did not significantly increase the ductility of the beams, it approximately doubled their load capacities. The results of the experimental study were compared to the ones obtained from nonlinear finite element analysis (NLFEA) and it was observed that they were compatible. Finally, it can be concluded that the devised method could be applied to structural members as an alternative to methods in application due to lightness, low-cost, easy applicable and reliable.

Keywords

Acknowledgement

Supported by : Celal Bayar University

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