Experimental and numerical investigation on the flexural behavior of concrete-filled elliptical steel tube (CFET)

Concrete-filled elliptical steel tube (CFET) is a novel type of composite member, which has great potential to be used as piers and columns in bridges airport terminals because its low flow resistance coefficient reasonable distribution major-minor axis. Pure bending loading conditions are not frequently occurred practical engineering, but the flexural researches important since it's basis mechanical property under complex loading. However, little attention behavior CFETs been paid at present. Hence, main objective this paper presents combined experimental numerical investigation on CFETs. Flexural tests were carried out investigate bending. The moment vs. curvature curves during whole process was analyzed detail, all specimens behaved very ductile manner. Besides, action between core concrete discussed clarified based results. Furthermore, FE (Finite element) model with precise material constitutive models established comprehensively, terms full analysis curves, development stress strain concrete, action. It should noted that there existed bond slip interface process. Then, parametric studies various factors performed. Finally, design formulas proposed predict ultimate stiffness predicted results showed satisfactory agreement Moreover, difference among experimental, using related codes illustrated. study expected provide reliable reference for application concrete-filled (CFST) structures.