Ultimate Strength of Concrete Filled Square Steel Tubular Beam-Columns

Abstract

<jats:p>The objective of this study is to examine the ultimate strength of CFT columns. The range of the axial load ratio and the slenderness ratio in which CFT beam-columns reach the full plastic moment are examined on the basis of the strength formulas specified by AIJ Recommendation for Limit State Design of Steel Structures. The CFT columns are subjected to the constant axial compressive force and the monotonic moment at the one end, as the analytical parameters the axial load ratio and slenderness ratio are selected. The analysis is carried out by the shooting method. Bending moment-rotational angle relationships are calculated by the shooting method and the maximum strengths of CFT columns are obtained. When the value obtained by multiplying the axial load ratio and the second power of the slenderness ratio is 0.05, the maximum strength reach 95% of the full plastic moment under the condition that the axial load ratio value is less than or equal to 0.75. When the value obtained by multiplying the axial load ratio and the second power of the slenderness ratio is 0.1, the maximum strength reach 95% of the full plastic moment under the condition that the axial load ratio value is less than or equal to 0.5.</jats:p>

Shear force‐deformation relationship of concrete‐filled square steel tube beam‐columns under monotonic lateral loading

“…Table 1 summarizes the experimental data from previous researches 8–18 used to examine the shear strength and deformation at each point in the proposed model of the shear force‐deformation relationship. The experimental data are the shear strength and deformation results of previous researches based on the monotonic loading and the first cycle of cyclic flexural‐shear loading tests under a constant axial force using square CFT beam‐column specimens.…”

Behavior of square concrete‐filled steel tubular beam‐columns subjected to lateral loads with constant cyclic displacement

“…Previous experimental studies on CFT columns subjected to constant amplitude of rotation angles were conducted before the abovementioned study. [10][11][12] However, these studies all used approximately ten repeated cycles, which is too small a number to examine the structural performance of CFT columns subjected to long-period earthquake ground motions.…”

“…14,15 Furthermore, we presented summaries 16 of the relationship between the lateral load and rotation angle and the load deterioration behavior of CFT columns provided in previous studies. [9][10][11][12]14 The purpose of the study presented in this paper was to clarify the structural performance of slender CFT columns subjected to cyclic loading with constant displacement amplitude under constant axial loads. A systematic experiment was conducted using the effective length factor-section depth ratio, axial load ratio, and the rotation angle as test parameters.…”