Advanced Steel Construction

Vol. 3, No. 1, pp. 443-458(2007)




S.T. Lie *, Z.M. Yang, S.P. Chiew and C.K. Lee

School of Civil and Environmental Engineering, Nanyang Technological University

50 Nanyang Avenue, Singapore 639798, Singapore

Tel: +65-6790-5284; Fax: +65-6792-1650

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

Received: 28 October 2006; Revised: 20 May 2006; Accepted: 22 May 2006 




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The ultimate static strength of tubular joints is usually calculated at the design stage based on empirical formulae incorporating the joint geometry, loading mode and materials strength. However, fatigue cracks have been detected in some aging structures, which tend to reduce the static strength. Methods for predicting the loss of strength of cracked tubular joints are therefore very important in practice. Very few published results are available concerning the residual strength of cracked square hollow section (SHS) joints. In order to develop guidelines on assessing the static strength of fatigue-cracked square hollow section (SHS) joints, a range of numerical analysis and full-scale test has been carried out on cracked and uncracked T-joints. The non-linear elastic-plastic finite element (FE) technique has been employed successfully for calculating the plastic collapse loads of uncracked and cracked T-joints under axial load at the brace end. Accordingly, anapproach to predict the ultimate strength of cracked SHS T-joints is proposed in this paper. The experimental test results, conducted at room temperature, have confirmed and agreed well with the FE analysis findings. 



crack; finite element technique; non-linear analysis; square hollow section (SHS); T-joints; ultimate strength


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