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Materials and Structures

, Volume 38, Issue 10, pp 857–864 | Cite as

Performance of hybrid rebars as longitudinal reinforcement in normal strength concrete

  • B. Saikia
  • J. Thomas
  • A. Ramaswamy
  • K. S. Nanjunda Rao
Scientific Reports

Abstract

Although steel is most commonly used as a reinforcing material in concrete due to its competitive cost and favorable mechanical properties, the problem of corrosion of steel rebars leads to a reduction in life span of the structure and adds to maintenance costs. Many techniques have been developed in recent past to reduce corrosion (galvanizing, epoxy coating, etc.) but none of the solutions seem to be viable as an adequate solution to the corrosion problem. Apart from the use of fiber reinforced polymer (FRP) rebars, hybrid rebars consisting of both FRP and steel are also being tried to overcome the problem of steel corrosion. This paper evaluates the performance of hybrid rebars as longitudinal reinforcement in normal strength concrete beams. Hybrid rebars used in this study essentially consist of glass fiber reinforced polymer (GFRP) strands of 2 mm diameter wound helically on a mild steel core of 6 mm diameter. GFRP stirrups have been used as shear reinforcement. An attempt has been made to evaluate the flexural and shear performance of beams having hybrid rebars in normal strength concrete with and without polypropylene fibers added to the concrete matrix.

Keywords

Failure Load Fiber Reinforce Polymer Concrete Beam Carbon Fiber Reinforce Polymer Glass Fiber Reinforce Polymer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Résumé

Bien que l'acier soit communément utilisé comme matériau de renforcement en raison de la compétitivité de son coût et de ces propriétés mécaniques avantageuses, le problème de la corrosion de barres en acier conduit à une réduction de la durée de vie de la construction et augemente les coûts d'entretien. De nombreuses techniques ont été récemment développées afin de réduire la corrosion (galvanisation, revêtement par peinture aux résines époxydiques, etc.) mais aucune de ces solutions ne semble viable pour lutter au mieux contre le problème de la corrosion. À part l'utilisation de barres d'armature en polymères renforcés de fibres (PRF), des barres d'armature hybrides composées à la fois de PRF et d'acier sont également testées pour surmonter le problème de la corrosion de l'acier. cet article évalue les performances de barres d'armature hybrides en tant que renforcement longitudinal dans des poutres de béton à résistance normale. Les barres hybrides utilisées dans ce travail sont principalement constituées de paquets de polymères renforcés de fibres de verre (GFRP) de 2 mm de diamètre orientés suivant une configuration hélicoïdale, autour d'une carotte d'acier doux de 6 mm de diamètre. Des étriers en polymères renforcés de fibres de verre ont été utilisés comme renforcement au cisaillement. On a essayé d'évaleur le comportement en flexion et cisaillement de poutres de béton à résistance normale comportant des barres d'armature hybrides, avec et sans addition de fibres de polypropylène à la matricedu béton.

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Copyright information

© RILEM 2004

Authors and Affiliations

  • B. Saikia
    • 1
  • J. Thomas
    • 1
  • A. Ramaswamy
    • 1
  • K. S. Nanjunda Rao
    • 1
  1. 1.Department of Civil EngineeringIndian Institute of ScienceBangaloreINDIA

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