Analytical Studies of Concrete-Filled Circular Steel Tubes under Axial Compression

Abstract

This paper describes a numerical program to analyze the behavior of the concrete-filled steel tubular (CFT) stub columns, and predict various modes of lateral interactions between steel tube and filled-in-concrete under axial compression. The behavior of the CFT columns is controlled by both the strength and the confinement effect of steel tube and filled-in-concrete in the columns. Various lateral interactions between steel tube and filled-in-concrete in CFT columns are classified into eight different cases by the contact between steel tube and filled-in concrete at different stress stages. The paper examines the analytical models with various experimental results in literature. The comparisons showed that the numerical program is reasonable to capture mechanical behavior of concrete-filled circular steel tubes.