KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Prediction of Failure Strength of Reinforced Concrete Deep Beams using Two-dimensional Grid Strut-Tie Model Method

2차원 격자 스트럿-타이 모델 방법에 의한 철근콘크리트 깊은 보의 파괴강도 예측

  • 윤영묵 (경북대학교 토목공학과) ;
  • 권상혁 ((주)태영건설 원가관리팀) ;
  • 채현수 ((주)한길아이티 인프라팀)
  • Received : 2015.05.25
  • Accepted : 2016.03.11
  • Published : 2016.08.01
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Abstract

It is difficult to form a rational strut-tie model that represents a true load transfer mechanism of structural concrete with disturbed stressed region(s). To overcome the difficulty and handle numerous load cases with just one strut-tie model, a two-dimensional grid strut-tie model method was proposed previously. However, the validity of the method was not fully examined, although the incorporated basic concepts and new methods regarding the effective strength of concrete strut, load carrying capacity of struts and ties, and geometrical compatibility of grid strut-tie model were explained in detail. In this study, for accurate strength analysis and reliable design of reinforced concrete deep beams, the appropriateness of the two-dimensional grid strut-tie model method is verified. For this, the failure strength of 237 reinforced concrete deep beams, tested to shear failure, is predicted by the two-dimensional grid strut-tie model method, and the results are compared with those obtained by the sectional shear design methods and conventional strut-tie model methods of current design codes.

스트럿-타이 모델 방법을 이용한 콘크리트 구조부재의 설계 시 구조부재 내부의 하중전달 메커니즘을 대변하는 스트럿-타이 모델을 형성하는 일은 어렵다. 스트럿-타이 모델 형성의 어려움을 극복하고 하나의 스트럿-타이 모델을 이용하여 다양한 여러 하중조합을 고려하고자 2차원 격자 스트럿-타이 모델 방법이 제안되었으나, 이 방법에 도입된 스트럿의 유효강도 결정방법, 스트럿과 타이의 하중전달능력 결정방법, 그리고 스트럿-타이 모델의 기하학적 적합조건 검토방법 등을 비롯한 몇 가지의 기본개념에 관한 내용만 소개되었을 뿐 이 방법의 타당성 검증에 대한 연구는 매우 미흡하다. 따라서 이 연구에서는 철근콘크리트 깊은 보의 정확한 해석과 경제적이고 안전한 설계를 위하여 기 제안된 2차원 격자 스트럿-타이 모델 방법의 적합성을 검증하였다. 이를 위하여 파괴실험이 수행된 다수의 철근콘크리트 깊은 보의 파괴강도를 2차원 격자 스트럿-타이 모델 방법, 현행 설계기준의 단면법, 그리고 현행 설계기준의 전통적인 스트럿-타이 모델 방법으로 예측하였으며, 그 예측 결과의 비교분석을 통해 기제안된 2차원 격자 스트럿-타이 모델 방법의 타당성을 평가하였다.

Keywords

References

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