Fire Resistance of Concrete Filled Double Skin Tubular Columns under Axial Load

일정 축력을 받는 Double CFT기둥의 내화성능 평가

  • 정상근 (서울시립대학교 구조연구실) ;
  • 김선희 (서울시립대학교 구조연구실) ;
  • 이성희 (서울시립대학교, (주)티섹구조엔지니어링) ;
  • 최성모 (서울시립대학교 건축학부)
  • Received : 2010.06.17
  • Accepted : 2011.02.21
  • Published : 2011.02.28

Abstract

Although an uncoated CFT column with a high axial-force ratio can be used to secure fire resistance for two hours or less in low-rise buildings, it does not satisfy the three-hour-long fire resistance required in high-rise buildings. Accordingly, so that the uncoated CFT column could be used for high-rise buildings, additional measures for the improvement of its fire resistance should be proposed. In this regard, the use of a Double CFT column as a measure for improving the fire resistance of the uncoated CFT column was proposed in this paper. A fire resistance test was conducted on an uncoated CFT column and a Double CFT column in real scale, under a load. Through such test, the effect of the Double CFT column on fire resistance was evaluated and then compared with that of a variant shape of the cross-section of a steel column.

높은 축력비가 적용된 무피복 CFT기둥은 보통 중저층 건물에서 2시간 이하의 내화성능을 확보하는데 적용 가능하나, 고층건물에서 요구되는 3시간의 내화성능을 만족시키지는 못한다. 따라서 고층건물에 무피복 CFT기둥을 적용하기 위해서는 추가적인 내화성능 향상방안이 제시되어야 한다. 이에 본 연구에서는 무피복 CFT기둥의 내화성능 향상방안으로써 Double CFT기둥을 설정하였다. 본 연구에서는 실대크기의 무피복 CFT기둥과 Double CFT기둥에 대한 재하가열실험을 수행하였다. 이를 통해, Double CFT기둥의 적용에 따른 내화성능 향상 효과 및 강관의 단면형상 변화에 따른 영향을 비교 평가해 보고자 한다.

Keywords

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