Design buckling resistance of angle sections
Advisory Desk Note 542
Document Status
Current
Supplement
Civil & Structural Supplement
Series
Advisory Desk Note
Abstract
This SCI Advisory Note clarifies the distinction between flexural and torsional buckling resistances used for angle sections in the Blue Book. It explains that flexural buckling resistance (F) accounts for torsional-flexural effects and varies with member length, while torsional buckling resistance (T) does not, due to the absence of a warping term in angle sections. The note derives expressions for torsional resistance based on critical axial load, emphasising that warping is negligible for thin, intersecting rectangular elements. It references Eurocode guidance for effective slenderness in practical design, offering simplified methods for accounting for complex buckling interactions.
History
April 2025 edition.
Subjects
- Steel building systems/frame
- Building systems/frame
- Building structure
- Metal sections/other items
- Steel
- Materials
Publisher History
With over 30 years experience, the Steel Construction Institute provide technical expertise and best practice to the steel construction sector.
Information
NBS
NBS has produced specification systems and information products for construction industry professionals for more than 40 years. The National Building Specification is the recognised UK national standard and is used by over 5,000 organisations. NBS is part of RIBA Enterprises Ltd.
Accuris
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