Local buckling of S700 high strength cold-formed steel built-up I-sections subjected to combined compression and minor-axis bending
Author(s)
Ma, Chicheng
Su, Andi
Jiang, Ke
Zhao, Ou
Gardner, Leroy
Type
Journal Article
Abstract
This paper presents an experimental and numerical study into the cross-section behaviour and strength of S700 high strength cold-formed steel built-up I-section stub columns under combined compression and bending. An experimental programme, including tensile coupon tests, measurements of initial local geometric imperfections and ten minor-axis eccentric compression tests, is first presented. A numerical modelling study, in which finite element models were developed, validated against the eccentric compression test results and used to conduct parametric studies, is then described. The experimental and numerical results were used to assess the applicability of existing European and North American codified design interaction curves to S700 high strength cold-formed steel built-up I-section stub columns under combined loading. The evaluation results revealed that (i) the codified effective width expressions yielded conservative end points for the design interaction curves (i.e. the cross-section resistances under pure compression and pure bending) and thus overly conservative ultimate load predictions, while (ii) the direct strength method resulted in more accurate ultimate load predictions, but still with conservative bending end points. Finally, a modified design expression was assessed and shown to provide improved predictions of ultimate loads over the design codes for S700 high strength cold-formed steel built-up I-section stub columns under combined compression and bending.
Date Issued
2026-02-01
Date Acceptance
2025-10-27
Citation
Thin-Walled Structures, 2026, 219 (Part A)
ISSN
0263-8231
Publisher
Elsevier
Journal / Book Title
Thin-Walled Structures
Volume
219
Issue
Part A
Copyright Statement
Copyright © 2025 Elsevier Ltd. This is the author’s accepted manuscript made available under a CC-BY licence in accordance with Imperial’s Research Publications Open Access policy (www.imperial.ac.uk/oa-policy)
License URL
Subjects
BEAMS
Built-up I -section stub columns
CHANNEL SECTIONS
COLUMNS
DESIGN
Eccentric compression tests
Engineering
Engineering, Civil
Engineering, Mechanical
Mechanics
NONLINEAR BEHAVIOR
Numerical modeling
S700 high strength cold-formed steel
Science & Technology
Structural design
Technology
Publication Status
Published
Article Number
114166
Date Publish Online
2025-10-27