Experimental and numerical studies of concrete-filled corrugated steel tubular column under axial compression

Abstract

This paper proposed a novel composite structure of concrete-filled corrugated steel tubular column with polygonal steel tubes (CFCST-PST), which consisted of concrete and multi-cell steel tubular column, includingpolygonalsteeltubesandcorrugatedsteelplates. This new column enables the confinement of multi-cell steel tubular column to the core concrete in addition to preventing local buckling of the tubes. To investigate the axial compression mechanical properties of the column and the capabilities of polygonal steel tubes, a concrete-filled corrugated steel tubular column with square steel tubes (CFCST-ST) was designed and fabricated as a comparative specimen. Axial compression experiments and finite element studies (FEM) were carried out on both CFCST-PST and CFCST-ST specimens. Through the previous research, it was found that CFCST-ST has better ductility and higher bearing capacity, while the corrugated plate with higher lateral stiffness, so that concrete is well restrained. In this paper, research had revealed that CFCST-PST effectively expands the strongly confined area of core concrete, as compared to CFCST-ST. A detailed discussion of the strain development of the corrugated plates was presented in order to demonstrate the confinement effect. Finally, the method of confining stress homogenization was used to establish formulas for calculating the axial compression load capacity of CFCST-PST for engineering purposes.