Papers abstract:

This paper describes the finite element method using ABAQUS to model the axial compressive behavior of inclined, tapered, and straight–tapered–straight (STS) concrete-filled steel tubular stub (CFST) columns with square hollow sections. The accuracy of the numerical model was verified by comparing the numerical predictions with an experimental study of the 200×200×3.75 RHS filled with C60 concrete with an inclined angle of 0–9° and a tapered angle of 0–4°. The results show that the compressive behaviors, load vs. strain relationship, and failure mode predicted by the numerical simulations were agreeable with experimental results. After the validation, a parametric study was performed with three typical steel hollow sections (200×200×3.75 RHS, 300×300×6.3 RHS, and 400×400×8.0 RHS) and extended the inclined angle and tapered angle to 0–15° and 0–12°, respectively. The parametric study highlights some of the behavior observed in the test and extends the application range. In addition, a reduction factor for calculating the axial capacity of this form of CFST columns is proposed.

Product Overview:
This tutorial provides a step-by-step guide to simulate an inclined CFST column under axial compression, replicating the methodology from the referenced ISI paper. Key simulation steps include:

• Creation of 3D deformable concrete core and steel shell with adjustable inclination.
• Assignment of material properties (Concrete Damaged Plasticity for concrete, elastic-plastic steel).
• Application of boundary conditions (fixed base, displacement-controlled top loading).
• Meshing (fine global seed size for accuracy) and analysis types (Dynamic Explicit and Static General).
• Extraction of force-displacement curves and buckling behavior visualization.

In this tutorial, local buckling and axial load capacity are simulated, according to data from the work of Lam et al.