Answers are grounded in this paper and cite their sources.
The Elastic-Plastic Behavior of Pin-Ended, Concrete-Filled Steel Tubular Columns, Loaded Either Symmetrically or Unsymmetrically About Either of the Two Axes Is Studied Using the Column Curvature Curve Method. Two Types of Cross Section Are Considered: Circular Shapes and Square Shapes. Three Types of Stress-Strain Relationship for Concrete Are Studied: (A) Uniaxial State of Stress; (B) Triaxial State of Stress, the Effect Being Assumed to Increase the Ductility Only; (C) Triaxial State of Stress, the Effect Being Assumed to Increase Both the Ductility and Strength. The Results Obtained Are Compared With Those From Tests Reported Elsewhere, and Good Agreement Is Observed. /Author/
No takes yet. Share an insight, caveat, or question.
Chen et al. (1973) studied this question.