Numerical Analysis on Mechanical Properties of Different Fiber-Reinforced Cold-Formed Steel-Concrete Composite Corner...

Area of Science:

• Structural Engineering
• Materials Science
• Civil Engineering

Background:

• Conventional cold-formed steel-concrete (CFS-C) corner columns suffer from brittle failure.
• Fiber-reinforced concrete (FRC) offers a potential solution to enhance performance.

Purpose of the Study:

• Investigate failure mechanisms and performance of CFS-C corner columns using FRC.
• Evaluate the impact of various fiber types and dosages on axial compression capacity and displacement.

Main Methods:

• Developed and validated a finite element model (FEM) against experimental data.
• Conducted parametric analyses on polypropylene fiber (PF), carbon fiber (CF), steel fiber (SF), and bamboo fiber (BF) dosages and cold-formed steel (CFS) thickness.

Main Results:

• Polypropylene fiber effectiveness depends on steel thickness, increasing capacity by 24.8% with thicker steel.
• Carbon fiber shows a critical dosage (0.4%), increasing capacity by 14.1% but decreasing with higher dosages due to agglomeration.
• Steel fiber significantly increases ultimate capacity by 36.5% and displacement by 92.2% at 1.6% dosage.
• Bamboo fiber primarily enhances ductility, increasing displacement by 33.2% through crack bridging.
• Modified Eurocode 4 formula reduces calculation error for ultimate capacity to within 1%.

Conclusions:

• Fiber-reinforced concrete significantly improves the performance of CFS-C corner columns.
• Steel fibers provide the most substantial gains in both strength and ductility.
• Optimal fiber selection and dosage are crucial for maximizing performance benefits.
• The findings support the use of FRC in CFS-C columns for seismic and load-bearing applications.
• Validated numerical models and improved design formulas enhance the reliability of CFS-C composite structures.