Parametric Study on the Behavior of Steel Tube Columns with Infilled Concrete—An Analytical Study

Concrete-filled steel tube (CFST) columns are used in tall buildings and bridges, they provide more rigidity higher bearing capacity, but buckling affects their behavior. There is an exceptional need to study the behavior of these under various conditions. The numerical method beneficial supplementing experimental works explore effects parameters because limitations cost, apparatus, time program. parameters, such as different slenderness ratios, i.e., column-height-to-cross-section-dimension (H/D), steel-tube-thickness-to-column-dimension (D/t), compressive strength concrete yield ratio (fc/fy) concentric axial loading considered this current study. Firstly, a finite element model “ANSYS” software program was constructed validate results works. extensive models were carried out extensively widen field. work conducted on sixty-four specimens. Moreover, analytical calculations from international codes/standards compared with test reliability predicting ultimate carrying loads. provided that show improvement effect CFST high infilled concrete, while no remarkable enhancement observed. Increasing columns’ diameter effective enhancing load capacity (about three times more) than increasing thickness 1.3 times). Ring stiffeners for long (H/D > 12) do not lead any column due yielding occurring firstly at location rings. ECP205-2007 most conservative design code columns, AIJ good failure other codes/standards. Eurocode 4 provides underestimation values load-carrying columns.