고강도콘크리트를 충전한 CFT 기둥의 내화성능 평가에 관한 실험적 연구

CFT(Concrete filled steel tube, below CFT) is an excellent internal force and deformation capacity. But it is difficult to evaluate the fire resistant performance of the CFT. Because two main materials such as steel tube and concrete are combined as one. Also, the case of high strength CFT is feared that spalling occur inside. In this study, types of CFT(column) specimens were four factors which were strength of concrete, slenderness ratio of steel tube, fiber using, fire protective coating and then CFT(column) specimens were exposed to heating controlled as closely as possible the ISO-834 standard fire curve. Also, test results tried to analyze internal temperature through nonlinear transient heat flow analysis. Test results showed relative values of CFT specimens and analysis but surface parts were excessive values of analysis. Moreover, fire-resist design of CFT column comes to the conclusion that is sufficient consideration. Because results tend to indicate different properties.