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Interface Behavior of Concrete Infilled Steel Tube Subjected to Flexure

휨을 받는 콘크리트 충전 강관의 계면거동

  • 이타 (쌍용건설(주) 토목기술팀) ;
  • 정종현 (건국대학교 토목공학과 대학원) ;
  • 김형주 (건국대학교 토목공학과 대학원) ;
  • 이용학 (건국대학교 토목공학과)
  • Received : 2014.03.12
  • Accepted : 2014.12.23
  • Published : 2015.02.01

Abstract

Interface behavior of concrete-infilled steel tube (CFT) was investigated based on the experimental observations and numerical analyses. Laboratory tests were performed for twelve CFTs that consisted of two different cases of diameters where each diameter case was composed of three different cases of shear span length. Thereby, diameter and shear span parameters were considered to prove the question of whether there exists interface slip between steel tube and infilled-concrete. Confining effect of steel tube to infilled concrete was also investigated by measuring lateral strain as well as longitudinal strain. Based on the study, it was concluded that confining effect of steel tube to infilled-concrete is not influential under flexural loading and therefore, the sectional analysis is an effective way to estimate the flexural strength of CFT.

강-콘크리트 슬립실험으로 결정된 계면 계수값을 휨하중을 받는 콘크리트 충전강관 실험의 결과예측에 적용하여 콘크리트 충전강관의 계면거동과 구속효과를 평가하였다. 이를 위해 ${\phi}100mm$${\phi}200mm$의 두 종류 강관 직경을 갖는 콘크리트 충전 강관(CFT)을 제작하여 휨 거동실험을 수행하였으며, 계면거동을 고려하는 유한요소 해석을 수행하여 거동을 예측하였다. 실험 및 해석결과의 분석을 통해 충전 콘크리트에 대한 강관의 구속효과는 강도의 계산에서 고려할 만한 정도의 영향성은 없는 것을 확인하였다. 또한, 강관과 충전콘크리트 간의 계면슬립변위는 하중 재하점 부근에서 가장 크게 발생하고 단부에 가까울수록 감소하며 전단지간 내의 계면에 작용하는 부착력이 단부에서 콘크리트의 압출을 억제함을 유한요소해석 결과를 통해 확인하였다.

Keywords

References

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