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Analytical Study on the Flexural Strength of CFS Reinforced Concrete Beams under Service Loads

사용하중을 받는 RC보의 탄소섬유 휨 보강에 관한 해석적 연구

  • Yoon, Tae-Ho (Department of Architectural Engineering, Changwon University) ;
  • Kang, Kyung-Soo (Department of Architectural Engineering, Dongmyung University)
  • Received : 2011.05.30
  • Accepted : 2011.08.11
  • Published : 2011.08.31

Abstract

In this study flexural strength of damaged concrete beams reinforced by CFS is analysed. Nonlinear section analysis is used to include stress status of tension bars and compressive concrete under loads acting on the original member at the time of strengthening. Calculated flexural strength is compared with Sin-Hong formula which is frequently used in CFS reinforcement design. Nonlinear analysis with variation of the number of strengthening CFS, the ratio of tensile reinforcement, the ratio of section dimension shows that the flexural strength of CFS reinforced beams much depends on reinforcing stage. From the result of this analysis, the flexural strength of CFS reinforced concrete beam is reduced according to the magnitude of pre-loaded service loads.

본 연구에서는 사용 중에 있는 철근콘크리트 보의 사용하중 단계에 따른 탄소섬유 보강 후의 휨보강 효과를 분석 고찰하였다. 사용하중을 받는 RC 보의 탄소섬유시트 보강에 따른 원부재와의 초기변형률 차이와 하중상태에 따른 잔류변형률의 영향을 고려하고, 보강 후 거동에 영향을 미치는 해석변수들에 대한 비선형 단면해석을 수행하여, 보강단계에 따른 보강보의 거동특성 및 보강효과에 대해 고찰하고, 기존 실무에서 보강설계시 가장 많이 사용되는 신영수-홍건호식과 비교 검토하였다. 보강 겁수, 인장철근비, 단면치수비를 변수로 한 변수 해석을 수행하여 보강단계에 따른 휨강도의 변화를 확인하고 보강 시기에 따른 휨강도를 계산하고 휨보강 효과를 분석하였다.

Keywords

References

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