Formulae for calculating elastic buckling loads for web crippling of rectangular hollow sections
File(s)
Accepted version
Author(s)
Dai, R
Gardner, L
Wadee, MA
Type
Conference Paper
Abstract
Formulae for determining the elastic buckling loads of structural steel rectangular hollow sections (RHS) subjected to concentrated transverse forces are presented herein. The predicted elastic buckling load is bounded by a theoretical lower bound, where only the material within the bearing length is mobilised, and a practical upper bound, where the adjacent material is mobilised to its maximum extent. The lower bound is the elastic buckling load of a wide plate with a width equal to the bearing length and a length equal to the web depth, while the upper bound is determined from finite element (FE) analyses of various representative loading scenarios. The level of mobilisation of adjacent material (i.e., where a specific case lies between the lower and upper bounds) is quantified by introducing a coefficient ζ that is calibrated through FE analyses in the commercial package ABAQUS. The rotational stiffness afforded to the webs by the flanges is also captured. The four loading scenarios defined in the North American Specification (NAS) and Australian/New Zealand Standard (AS/NZS) for the design of cold-formed steel structures, namely the Interior-Two-Flange (ITF), End-
Two-Flange (ETF), Interior-One-Flange (IOF) and End-One-Flange (EOF) loading conditions, alongside their transitional cases, are considered. Rectangular hollow sections with a broad spectrum of cross-sectional geometric proportions and bearing lengths encompassing the aforementioned loading conditions are considered. It is found that the developed formulae for predicting the elastic buckling loads under concentrated transverse forces provide accurate results that are typically within 5% of the numerical values. Hence, the developed formulae can be employed as a convenient alternative to numerical methods in advanced structural design methodologies, such as the Direct Strength Method (DSM) and the Continuous Strength Method (CSM).
Two-Flange (ETF), Interior-One-Flange (IOF) and End-One-Flange (EOF) loading conditions, alongside their transitional cases, are considered. Rectangular hollow sections with a broad spectrum of cross-sectional geometric proportions and bearing lengths encompassing the aforementioned loading conditions are considered. It is found that the developed formulae for predicting the elastic buckling loads under concentrated transverse forces provide accurate results that are typically within 5% of the numerical values. Hence, the developed formulae can be employed as a convenient alternative to numerical methods in advanced structural design methodologies, such as the Direct Strength Method (DSM) and the Continuous Strength Method (CSM).
Date Issued
2025-08-20
Date Acceptance
2025-03-28
Citation
Engineering materials, structures, systems and methods for a more sustainable future, 2025, pp.256-262
ISBN
9781032780702
Publisher
Taylor & Francis
Start Page
256
End Page
262
Journal / Book Title
Engineering materials, structures, systems and methods for a more sustainable future
Copyright Statement
© 2025 Taylor & Francis Group. 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
Source
9th International Conference on Structural Engineering, Mechanics and Computation
Place of Publication
Boca Raton, USA
Publication Status
Published
Start Date
2025-09-01
Finish Date
2025-09-03
Coverage Spatial
Cape Town, South Africa
Date Publish Online
2025-08-20