Iterative Finite Element Analysis of Concrete-Filled Steel Tube Columns Subjected to Axial Compression

Abstract

Since laboratory tests are usually costly, simulating methods using computers are always under the spotlight. This study performed a finite element analysis (FEA) using iterative solutions for simulating circular and square concrete-filled steel tube (CFST) columns infilled with high-strength concrete and reinforced with a cross-shaped plate (comprising two plates along the columns that divide the hollow columns into four equal sections) with and without opening. For this reason and for validation purposes, the columns had length of 900 mm, width/diameter of 150 mm and wall thickness of 3 mm. In this study, unlike in some other studies, the cross-shaped plate was assumed to be fixed at the top and the bottom of a column, and the columns were subjected to axial compression pointed in the center. The outcomes revealed that the cross-shaped plate could improve the axial strength of both circular and square CFST columns; however, the structural performance of the square CFST columns changed: local outward buckling was observed after inserting the cross-shaped plate. By inserting an opening on the cross-shaped plate, the bearing capacity of the circular CFST columns was further improved, while the square CFST columns experienced a decline in their ultimate bearing capacity compared with the corresponding models without the opening. The lateral deflection also improved for the circular CFST columns by adding the reinforcement. However, for the square CFST columns, while it initially improved, increasing the thickness of the cross-shaped plate inversely influenced the lateral deflection of the square CFST columns. The results were also compared with some available codes, and a good agreement was achieved with those outcomes.

Numerical Analysis of the Axial-Flexural Behavior of CFST Columns with Active Transverse Prestressing

“…The structural behavior of the specimens presented in Section 2 is described with a model implemented in the finite element program ABAQUS 6.14-1 [19] using an implicit (standard) formulation. This software has been chosen as it is highly reputable and suitable for accurately reproducing complex structural behaviors; in this sense, it has been considered previously by several authors for the simulation of CFSTs [8,12,20].…”

Structural performance of the concrete-filled tube column with internal triangular units subjected to axial compression

“…The concrete-filled tube (CFT) column is a composite structural member, which is composed of the rectangular (or circular) steel tube and concrete filled inside the tube [1][2][3][4][5]. This combination is highly effective because the presence of the steel tube enhances the confinement effect of the infilled concrete.…”

Modeling and Calculation of Improved Centrifuged Reinforced Concrete Columns with Variotropic Structure

“…Many works are devoted to the study of the behavior of concrete and reinforced concrete columns under axial loading [29][30][31][32]. At the same time, numerical simulation methods [33][34][35], experimental methods [31], and complex methods are widely used to confirm the created models [29,30,[36][37][38][39][40][41][42]. The material of the columns is also quite diverse in these studies.…”

“…The material of the columns is also quite diverse in these studies. This can be ordinary reinforced concrete [29,30,32], high-strength concrete [31], high-strength steel-reinforced concrete [30,36], reinforced concrete from steel pipes with concrete filling [33][34][35]38,40,41], other types of concrete (fiber-reinforced, geopolymer [39], fiberglass [37], and others with various formulation solutions). Differences in existing studies also lie in the size of the columns.…”