Advanced Steel Construction

Vol. 15, No. 3, pp. 259-266 (2019)




Chi-King Lee 1, * and Sing-Ping Chiew 2

1 School of Engineering and Information Technology, University of New South Wales Canberra, Australia

2 Singapore Institute of Technology, Dover Campus, Singapore

* (Corresponding author: E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.)

Received: 02 October 2018; Revised: 26 February 2019; Accepted: 03 June 2019




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A review is given to the procedure suggested by the Eurocode 3 for the section properties calculations of thin-walled Class 4 slender steel sections consists of plate elements. Focus will be given to the effective width approach described in the Eurocode 3. The essential steps for the effective width calculation for single plate element subjected to different direct stress distribution are first given. It is then followed by a study that compares the two different procedures, namely the full iteration procedure and the simplified procedure adopted by Eurocode 3 for Class 4 slender section properties calculation. Calculation examples are then given to demonstrate the calculation steps for both the full and the simplified approaches. Results of the calculation examples indicate that while the simplified procedure eliminates the tedious iteration steps and is much more convenient for manual calculation, the full iteration method in general will lead to less conservative effective area and section modulus and thus could result in more economical design in practice.



Class 4 Slender Sections, Thin-walled steel sections, Effective width method, Effective area and modulus


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