Finite Element Analysis of Axial Compression Performance of Stainless Steel -Steel Tube Sandwich Concrete Columns

Abstract

A finite element analysis software, ABAQUS, was used to numerically analyze nine specimens with varying inner steel tube thickness and slenderness ratio to study the axial compression performance of stainless steel - steel tube sandwich concrete columns. The influence of each parameter on the axial compression behavior was explored. The simulation results aligned closely with the experimental results, with the ultimate bearing capacity prediction error within 5%. Bulging deformation consistently occurred on the upper outer steel tube. Increasing the inner steel tube thickness improved the ultimate bearing capacity up to 20%, with the 4-6 mm wall thickness range providing the most effective capacity increase. The ultimate bearing capacity deteriorated up to 5% as the slenderness ratio increased, but the axial compression stiffness markedly decreased due to overall instability. A relationship between the stability coefficient and slenderness ratio was proposed, and the calculation results showed excellent agreement.