Structural Analysis of CFST and DS CFST Using ANSYS Workbench
Keywords:
Concrete-Filled Steel Tubes, Dune Sand, Finite Element Analysis, ANSYS, Buckling, Sustainable ConstructionAbstract
Concrete-Filled Steel Tubes (CFSTs) have emerged as efficient structural members in modern construction due to their superior strength, stiffness, and ductility arising from the composite interaction between a steel tube and infilled concrete. However, the depletion of natural river sand, a primary component of conventional concrete, has raised sustainability concerns and prompted the search for alternative fine aggregates. In this context, dune sand, abundantly available in desert regions, offers potential as a sustainable replacement material. This thesis presents a comparative study of the structural performance of conventional CFST and Dune Sand Concrete-Filled Steel Tubes (DS CFST) through finite element analysis (FEA) conducted in ANSYS Workbench.
Both CFST and DS CFST models were developed with identical geometry (1000 mm height, 150 mm diameter, 5 mm steel thickness), material definitions, meshing strategies, and boundary conditions to ensure direct comparability. Static structural analyses evaluated maximum deformation and equivalent elastic strain, while eigenvalue buckling analyses assessed critical load multipliers and mode shapes. Results indicated that DS CFST exhibited nearly identical deformation (9.37 × 10⁻⁹ m vs. 9.40 × 10⁻⁹ m for CFST) and slightly lower strain (2.63 × 10⁻⁸ m/m vs. 2.84 × 10⁻⁸ m/m). DS CFST showed a marginally higher buckling load multiplier (4.05 × 10⁵), suggesting improved global stability.
The findings confirm that dune sand concrete can replace conventional concrete in CFSTs without compromising performance, while contributing to sustainable construction practices by reducing reliance on river sand. The study provides novel numerical evidence supporting DS CFST as a viable structural solution, particularly suited for sand-rich and desert regions. Limitations include the exclusive reliance on simulations and single geometry and future research should incorporate experimental validation, varied loading conditions, and extended geometrical configurations.
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References
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