Study on Structural Performance of Two Seam Cold-Formed Square CFT Column to Beam Connections with Internal Diaphragm

2-Seam 냉간성형 각형 CFT 기둥-보 내다이아프램 접합부의 구조성능에 관한 연구

  • 오헌근 (서울시립대학교 건축공학과) ;
  • 김선희 (서울시립대학교 건축공학과) ;
  • 최영환 (삼성물산 건설부문 토건ENG팀) ;
  • 최성모 (서울시립대학교 건축공학과)
  • Received : 2012.06.12
  • Accepted : 2012.08.12
  • Published : 2013.03.19


The construction of a moment connection for a rectangular hollow section (RHS) column and a H-shaped beam is difficult because the RHS is a closed section. When a inner diaphragm is used for such a connection, in general, it is installed after cutting the HSS columns, which results in increased construction work. This paper suggests a new fabrication method to overcome such problems: An inner diaphragm is welded to inside a C-shaped section first, and then a column is fabricated by welding two C-shaped sections. This fabrication method is superior to a classic method in terms of constructibility. An experimental and a numerical study using Ansys 9.0 were performed in order to compare the strength of connections with respect to the presence of concrete, the corner shape of diaphragm, and the axis of loading. The experimental results including initial stiffness and ultimate loads are reported and the analytical results including load transfer mechanism, degree of stress concentration, and strain distribution are also reported.


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