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A New Refined Truss Modeling for Shear-Critical RC Members (Part I) - lts derivation of Basic Concept -

전단이 지배하는 RC부재의 새로운 트러스 모델링 기법 연구 (전편) - 기본 개념 유도를 중심으로 -

  • Kim Woo (Dept. of Civil Engineering, Chonnam National University) ;
  • Jeong Jae-Pyong (Dept. of Civil Engineering, Chonnam National University) ;
  • Kim Dae-Joong (Dept. of Civil Engineering, Namdo Collage)
  • 김우 (전남대학교 토목공학과) ;
  • 정제평 (전남대학교 토목공학과) ;
  • 김대중 (전남도립남도대학)
  • Published : 2004.12.01

Abstract

This paper describes a new refined truss modeling technique derived based on the well-known relationship of V=dM/dx=zdT/dx+Tdz/dx in a reinforced concrete beam subjected to combined shear and moment loads. The core of the model is that a new perspective on the shear behavior can be gained by considering the variation of the internal arm length along the span, so that the shear resistance mechanism can be expressed by the sum of two base components; arch action and beam action. The sharing ratio of these two actions is determined by accounting for the compatibility of deformation associated to the two actions. Modified Compression Field Theory and the tension-stiffening effect formula in CEB/FIP MC-90 are employed in calculating the deformations. Then the base equation of V=dM/dx has been numerically duplicated to form a new refined truss model.

이 논문은 휨과 전단이 동시에 작용하고 있는 철근콘크리트 보에서 전단은 휨모멘트의 변화율(V=dM/dx)이라는 기본 관계식에 근거한 새로운 트러스모델링기법을 제안하는 것이다. 이 새로운 모델의 핵심은 보의 경간에서 내부 모멘트 팔길이의 변화를 고려함으로써, 보의 전단 저항 메커니즘을 아치작용과 보작용이라는 두 기본 성분의 합으로 표현할 수 있게 한 것이다. 이두 작용에 의한 전단 저항 구성비는 상호 변형 적합조건을 적용하여 계산하였는데, 이 때 수정압축장이론과 CEB/FIP MC-90의 인장강화효과 공식을 이용하였다. 이렇게 함으로써 전단과 모멘트 관계식 V=dM/dx을 수치적으로 복제할 수 있는 새로운 트러스모델을 결정하였다.

Keywords

References

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