CFST columns are structurally superior because the concrete inside the steel tubes prevents local buckling at the tubes and the tubes confine the concrete. And, the thickness of steel tube in CFST column has been thinner with development of high-strengh steel. The thinner the steel tube of a square CFST column is, the more local buckling is likely to occur. For this reason, we developed welded built-up square steel tube with stiffeners which are placed at the center of the tube width acts as an anchor. In this study, we conduct experimental test for three specimens of the 4m long span welded built-up square CFT column with parameters of L/D and D/t. And, the test results were compared with the analysis results by M-ϕ-P Program.

1. 서론
2. 이론해석
3. 구조실험
4. 분석 및 고찰
5. 결 론
References

• 이성희(특허청 특허심사1국 사무기기심사과 공학박사) | Lee, Seong-Hui
• 최성모(서울시립대학교 건축학부 교수) | Choi, Sung-Mo
• 김영호(㈜지승컨설턴트 기술연구소 공학박사) | Kim, Young-Ho Corresponding author