Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
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Minimum Torsional Reinforcement Ratio of Reinforced Concrete Members for Safe Design

안전한 설계를 위한 철근콘크리트 부재의 최소비틀림철근비

  • Kim, KangSu (Dept. of Architectural Engineering, University of Seoul) ;
  • Lee, DeuckHang (Dept. of Architectural Engineering, University of Seoul) ;
  • Park, Min-Kook (Dept. of Architectural Engineering, University of Seoul) ;
  • Lee, Jung-Yoon (Dept. of Architectural Engineering, Sungkyunkwan University) ;
  • Ju, HyunJin (Dept. of Architectural Engineering, University of Seoul)
  • 김강수 (서울시립대학교 건축학부) ;
  • 이득행 (서울시립대학교 건축학부) ;
  • 박민국 (서울시립대학교 건축학부) ;
  • 이정윤 (성균관대학교 건축토목공학부) ;
  • 주현진 (서울시립대학교 건축학부)
  • Received : 2013.07.05
  • Accepted : 2013.08.31
  • Published : 2013.12.31
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Abstract

Current design codes regulate the minimum torsional reinforcement requirement for reinforced concrete members to prevent their brittle failure. The minimum torsional reinforcement ratio specified in the current national code and ACI318-11, however, have problems in the minimum longitudinal reinforcement ratio for torsion, the equilibrium condition in space truss model, and a marginal strength, etc. Thus, in order to overcome such shortcomings, this study presents a rational equation for minimum torsional reinforcement ratio that can provide a sufficient margin of safety in design. The minimum torsional reinforcement ratio proposed in this study was compared to the test results available in literature, and it was confirmed that it gave a proper margin of safety for all specimens studied in this paper.

현행 설계기준들에서는 비틀림모멘트를 받는 철근콘크리트 부재의 취성적인 파괴를 방지하기 위하여 최소비틀림철근비를 규정하고 있다. 그러나, 국내 현행기준 및 ACI318-11에서 규정하고 있는 최소비틀림철근비 산정식은 종방향 최소철근비, 공간트러스모델의 역학적 평형관계 및 여유강도 확보 등의 측면에서 불합리한 문제점들을 내포하고 있다. 따라서, 이 연구에서는 이러한 문제점을 극복하기 위하여, 보다 합리적이고 충분한 강도여유율을 확보할 수 있는 최소비틀림철근비 산정식을 제안하였다. 또한, 제안식을 기존실험 결과와 비교하여 검증하였으며, 제안모델이 모든 대상실험체들의 최소비틀림철근비를 안전측으로 평가하는 것을 확인하였다.

Keywords

References

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