City Research Online

Abstract

This paper presents both experimental and numerical investigations on the axial compressive behavior of the innovative four-opening concrete filled sandwich steel tube (FCFSST) stub columns. A total of 13 specimens, categorized into two groups, were meticulously designed to test the structural behavior of FCFSST stub columns subjected to axial compression. The first group consisted of 7 specimens with a uniform cross-sectional width (B) of 200 mm, focusing on key parameters such as the width-to-thickness ratio of outer tube (β<inf>o</inf>), diameter-to-thickness ratio of inner tube (β<inf>i</inf>) and sectional opening ratio (ϕ). In contrast, the second group included 6 specimens aimed at investigating the influence of section size, with B ranging from 120 mm to 360 mm. The observed failure patterns involve outward local buckling of outer tube, crushing of sandwich concrete, as well as inward local buckling and/or ovalization occurring in inner tubes at analogous cross-section locations. Furthermore, it is found that β<inf>o</inf> and ϕ are critical factors for load vs. deformation curves and mechanical indices; conversely, B exhibits a moderate effect. A finite element (FE) model was developed through ABAQUS software to replicate the behavior of FCFSST stub columns subjected to axial compression, and was validated against experimental results. Ultimately, based on these experimental and numerical findings, formulae to predict axial compressive capacity of FCFSST stub columns were proposed, along with considerations regarding limitations related to width/diameter-to-thickness ratios (β<inf>o</inf> and β<inf>i</inf>) for design applications.

Publication Type:	Article
Additional Information:	© 2025. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/
Publisher Keywords:	Four-opening concrete filled sandwich steel tube (FCFSST), Stub column, Compressive behavior, Tests, Finite element (FE) simulation, Axial compressive capacity
Subjects:	T Technology > TA Engineering (General). Civil engineering (General)
Departments:	School of Science & Technology School of Science & Technology > Department of Engineering
SWORD Depositor:	Symplectic Administrator

Export

Downloads