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Fatigue Behavior of Concrete Beam Using CFRP Rebar

CFRP 보강근을 이용한 콘크리트 보의 피로거동

  • Zhang, Pei-Yun (Department of Civil Engineering, yanbian University) ;
  • Kim, Okk-Yue (Department of Architectural Engineering, Chungbuk National University) ;
  • Cui, Xian (Department of Civil Engineering, yanbian University)
  • Received : 2019.09.02
  • Accepted : 2019.12.11
  • Published : 2019.12.20

Abstract

Recently, research has been carried out into the use of carbon fiber reinforced polymer (CFRP), which has good tensile strength and corrosion resistance, as an alternative to rebar. But as of yet, the research into fatigue failure of CFRP is insufficient. In this paper, an analysis was performed of the mechanical behavior and failure patterns of CFRP reinforced concrete beams according to static and cyclic loads, in order to evaluate the safety and validity of CFRP rebar as an alternative material for rebar. The cyclic load ranged from 10 % to 70% of the ultimate load, and was loaded at a speed of 3Hz using a sine wave in the form of a three-point loading method. Through the static load test, the maximum load or stiffness of the beam was found to increase remarkably with the increase of the reinforcement, but the fatigue test showed that the number of repetitions decreased and the amount of deflection increased with the increase of the reinforcement.

최근 철근의 대체재로서 인장강도나 내부식성이 좋은 CFRP(carbon fiber reinforced polymer)를 이용한 연구가 활발히 진행되고 있다. 그러나 현재 피로 파괴에 대한 연구는 미비한 상태이다. 따라서 본 연구에서는 CFRP보강 콘크리트 보를 제작하여 정적 및 반복 하중에 따른 역학적 거동과 파괴형태를 분석하고 철근의 대체 재료로서 CFRP 보강근 사용에 대한 안전성과 타당성을 평가하도록 하였다. 반복하중의 범위는 극한하중의 10~70%를 취하고 3점 재하방식으로 sine파를 이용한 3Hz의 속도로 재하 하였다. 정적 실험결과 보강량의 증가에 따라 보의 최대하중이나 강성은 현저하게 증가하였지만 피로 실험결과 보강량의 증가에 따라 반복 횟수는 감소하고 처짐량은 증가하여 안전성은 다소 감소됨을 알 수 있었다.

Keywords

References

  1. Gao P. Experimental Study and Application on Fatigue Behaviors of CFRP Tendons Reinforced FRCC Flexural Components, [dissertation]. [Southeast (China)]:College of Civil Engineering Southeast University; 2016. 124 p.
  2. ACI 440.IR-06. Guide for the Design and Construction of Concrete Reinforced with FRP Bars. Farmington Hills(USA). American Concrete Institute, 2006.
  3. Seo DW. Han BS, Shin SW. Behaviour of One-Way Concrete Slabs Reinforced with Fiber Reinforced Polymer(FRP) Bars. Journal of the Korea Concrete Institute. 2007 Dec;19(6):763-71. https://doi.org/10.4334/JKCI.2007.19.6.763
  4. ACI 440.3R-04, Guide Test Methods for Fiber-Reinforced Polymers (FRPs) for Reinforcing or Strengthening Concrete Structures. 2004. p. 20-2.
  5. Kim JS, Kim KS. A study on ductility capacity of reinforced concrete beam without shear reinforcement using cockle shells as fine aggregate. Journal of the Korea Institute of Building Construction. 2005 Jun;5(2):139-46.