Journal of the Computational Structural Engineering Institute of Korea (한국전산구조공학회논문집)

Computational Structural Engineering Institute of Korea (한국전산구조공학회)
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Seismic Retrofit of Reinforced Concrete Structures Using Steel Braces and Moment Frames

가새와 강골조를 이용한 저층 RC 구조물의 내진보강

  • 훠 찌안 촘 (성균관대학교 건설환경시스템공학과) ;
  • 박경훈 ((주)CH엔지니어링) ;
  • 김진구 (성균관대학교 건설환경시스템공학과)
  • Received : 2010.04.13
  • Accepted : 2010.08.12
  • Published : 2010.10.31
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Abstract

In this study a seismic retrofit scheme for the reinforced concrete moment framed structures was investigated using steel bracing and moment frames. The analysis model structure is a 3-story 3-bay moment frame structure designed only for gravity load. The stress/strain concentration in brace-RC frame connection was investigated using finite element analysis. To prevent premature joint failure, steel moment frames were placed inside of middle bay of the RC frame. Two types of braces, steel braces and buckling restrained braces(BRBs), were used for retrofit, and the ductility and the strength of the structure before and after the retrofit were compared using nonlinear static and dynamic analyses. According to the analysis results, the strength and ductility of the structure retrofitted by the moment frames and braces increased significantly. The added steel frame did not contribute significantly to the increase of lateral strength mainly because the size is relatively small.

본 연구에서는 가새와 강골조를 이용하여 철근콘크리트 모멘트 골조의 내진성능을 보강하는 방법에 대하여 연구하였다. 해석모델은 중력하중에 대해서만 설계된 3층 3경간의 RC 모멘트 골조 건물이다. 먼저 유한요소해석을 이용하여 RC구조물과 가새 접합부의 응력/변형 분포 상태를 파악하고, 접합부의 응력 집중현상을 방지하기 위하여 철골 모멘트골조를 추가하여 보강설계를 수행하였다. 내진보강을 위한 가새는 일반 철골 가새와 비좌굴 가새의 두가지 종류의 가새를 적용하고, 보강 전후 구조물의 강도 및 연성도를 비선형 정적 및 동적해석을 통해 비교하였다. 해석결과에 따르면 추가되는 철골 모멘트골조와 가새를 동시에 사용할 경우 구조물의 강도 및 연성능력의 증가에 큰 효과가 있는 것으로 나타났다. 추가되는 철골 모멘트골조는 단면이 크지 않을 경우 강도의 증가에 큰 영향을 미치지 않는 것으로 나타났다.

Keywords

References

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