Papers abstract:

The behavior of thin-walled dodecagonal section double-skin concrete-filled steel tubes under bending was studied in this paper. Both experimental investigation and finite element analysis (FEA) were carried out. A total of seven specimens were tested with a beam length of 2000 mm. The width-to-thickness ratio of the outer steel tube ranged from 75 to 133. The load–displacement curves, failure mode, and ultimate capacity of test specimens were obtained. A finite element model was developed for the thin-walled dodecagonal section double-skin concrete-filled steel tube subjected to bending. The FEA results were verified against the test results, and a parametric study was conducted using the verified model. In addition, the suitability of Han’s method, Uenaka’s method, and the proposed method for thin-walled circular section double-skin concrete-filled steel tubes subjected to bending was also evaluated.

Product Overview:
This tutorial provides a step-by-step guide for simulating the bending behavior of dodecagonal double skin concrete-filled steel tubes (CFDST) using Abaqus. The model replicates the experimental and numerical study from the referenced ISI paper, ensuring accuracy and practical applicability. Key simulation steps include:

• Creation of dodecagonal cross-sections for outer/inner steel tubes and concrete core.
• Assignment of material properties (concrete damage plasticity, ductile steel).
• Application of boundary conditions (encastre support, displacement-controlled loading).
• Tie constraints for concrete-steel interaction (alternative: frictional contact).
• Static and explicit dynamic analyses for quasi-static and nonlinear failure simulation.
• Post-processing to extract force-displacement curves, stress distribution, and damage evolution

In this tutorial, the bending response of CFDST beams is simulated, according to data from the work of Chen et al.