Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
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Flexural Behavior of FRP Bar Reinforced HSC Beams with Different Types of Reinforcing Bar and Fiber

이질 보강근 및 섬유와 함께 보강된 FRP 보강근 보강 고강도 콘크리트 보의 휨 거동

  • Yang, Jun-Mo (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Shin, Hyun-Oh (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Min, Kyung-Hwan (School of Civil, Environmental and Architectural Engineering, Korea University) ;
  • Yoon, Young-Soo (School of Civil, Environmental and Architectural Engineering, Korea University)
  • 양준모 (고려대학교 건축사회환경공학부) ;
  • 신현오 (고려대학교 건축사회환경공학부) ;
  • 민경환 (고려대학교 건축사회환경공학부) ;
  • 윤영수 (고려대학교 건축사회환경공학부)
  • Received : 2010.11.23
  • Accepted : 2011.04.08
  • Published : 2011.06.30
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Abstract

Ten high-strength concrete beam specimens, which have various combinations of different types of flexural reinforcement and short fibers were constructed and tested. Six beams were reinforced with two layers of steel, CFRP, and GFRP bar combinations. The other four beams were reinforced with two layers of single type CFRP and GFRP bars, with steel and synthetic short fibers. An investigation was performed on the influence of the parameters on the load-carrying capacity, post cracking stiffness, cracking pattern, deflection behavior, and ductility. The low post cracking stiffness, large deflection, deep crack propagation, large crack width, and low ductility of FRP bar-reinforced beams were controlled and improved by positioning steel bars in the inner layer of the FRP bar layer. In addition, the addition of fibers increased the first-cracking load, ultimate flexural strength, and ductility as well as the deep propagating cracks were controlled in the FRP bar-reinforced concrete beams. The increased ultimate concrete strain of fiber-reinforced concrete should be determined and considered when FRP bar-reinforced concrete members with fibers are designed.

이질 보강근의 조합 및 섬유의 혼입을 변수로 한 10개의 고강도 콘크리트 보를 제작하고 구조 실험을 수행하고 균열 후 강성, 처짐, 균열 양상, 연성에 대한 거동을 살펴보았다. 6개 부재는 철근, CFRP 보강근, GFRP 보강근의 조합으로 2단 휨 배근되었고, 4개 부재는 CFRP 보강근 혹은 GFRP 보강근으로만 2단 배근되고 강섬유 및 합성 섬유를 혼입하였다. FRP 보강근 내측에 철근을 처짐 및 균열 제어용으로 하이브리드 배근함으로써 FRP 보강근 보강 보의 낮은 강성, 큰 처짐, 낮은 연성, 깊은 균열 및 넓은 균열폭을 제어할 수 있었다. 또한, 섬유의 혼입을 통해 FRP 보강근 보강 보의 빠르고 깊은 균열이 제어되고 연성 및 내하력이 향상되었다. 섬유 혼입된 FRP 보강근 보강 콘크리트 부재 설계 시 섬유 혼입에 의해 증가된 콘크리트의 극한 압축 변형률에 대한 고려가 필요함을 알 수 있었다.

Keywords

References

  1. American Concrete Institute (ACI), "Guide for the Design and Construction of Concrete Reinforced with FRP Bars," ACI 440.1R-06, Farmington Hills, MI, 2006, 44 pp.
  2. Canadian Standards Association (CSA), "Design and Construction of Building Components with Fibre Reinforced Polymers," CAN/CSA S806-02, Rexdale, Ont., Canada, 2002, 206 pp.
  3. Japan Society of Civil Engineers (JSCE), "Recommendation for Design and Construction of Concrete Structures Using Continuous Fiber Reinforcing Materials," Concrete Engineering Series 23, A. Machida ed., Tokyo, Japan, 1997, 325 pp.
  4. 이주하, 양준모, 윤영수, "2방향 슬래브의 성능 향상을 위한 집중 배근된 FRP 바의 적용," 콘크리트학회 논문집, 19권, 6호, 2007, pp. 727-734. https://doi.org/10.4334/JKCI.2007.19.6.727
  5. ASTM International, "Standard Test Method for Flexural Performance of Fiber-Reinforced Concrete (Using Beam with Third-Point Loading)," ASTM C1609-07, West Conshohocken, PA, 2007, 9 pp.
  6. Morgan, D. R., Mindess, S., and Chen, L., "Testing and Specifying Toughness for Fiber Reinforced Concrete and Shotcrete," Proc., 2nd Univ.-Industry Workshop on Fiber- Reinforced Concrete and Other Advanced Composites- Fiber-Reinforced Concrete-Modern Developments, N. Banthia and S. Mindess, ed., Toronto, 1995, pp. 29-50.
  7. Aiello, M. A. and Ombres, L., "Structural Performances of Concrete Beams with Hybrid (Fiber-Reinforced Polymer- Steel) Reinforcements," Journal of Composites for Construction, Vol. 6, No. 2, 2002, pp. 133-140. https://doi.org/10.1061/(ASCE)1090-0268(2002)6:2(133)
  8. Rashid, M. A., Mansur, M. A., and Paramasivam, P., "Behavior of Aramid Fiber-Reinforced Polymer Reinforced High Strength Concrete Beams under Bending," Journal of Composites for Construction, Vol. 9, No. 2, 2005, pp. 117-127. https://doi.org/10.1061/(ASCE)1090-0268(2005)9:2(117)
  9. Rafi, M. M., Nadjai, A., and Ali, F., "Experimental Testing of Concrete Beams Reinforced with Carbon FRP Bars," Journal of Composite Materials, Vol. 41, No. 22, 2007, pp. 2657-2673. https://doi.org/10.1177/0021998307078727
  10. Theriault, M. and Benmokrane, B., "Effects of FRP Reinforcement Ratio and Concrete Strength on Flexural Behavior of Concrete Beams," Journal of Composites for Construction, Vol. 2, No. 1, 1998, pp. 17-16. https://doi.org/10.1061/(ASCE)1090-0268(1998)2:1(17)
  11. American Concrete Institute (ACI), "Design Considerations for Steel Fiber Reinforced Concrete," ACI 544.4R-88 (Reapproved 1999), Farmington Hills, MI, 1988, 18 pp.
  12. Alsayed, S. H. and Alhozaimy, A. M., "Ductility of Concrete Beams Reinforced with FRP Bars and Steel Fibers," Journal of Composite Materials, Vol. 33, No. 19, 1999, pp. 1792-1806. https://doi.org/10.1177/002199839903301902
  13. Naaman, A. E. and Jeong, S. M., "Structural Ductility of Concrete Beams Prestressed with FRP Tendons," Proceedings of the Second International RILEM Symposium (FRPRCS-2): Non-Metallic (FRP) for Concrete Structures, Ghent, Belgium, 1995, pp. 379-386.

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