Advanced Steel Construction

Vol. 4, No. 2, pp. 134-146 (2008)


STRESS ANALYSIS AND FATIGUE TEST ON PARTIALLY OVERLAPPED CHS K-JOINTS

 

T. Sopha, T.B.N. Nguyen, S.P. Chiew 1,*, C.K. Lee and S.T. Lie

1 School of Civil and Environmental Engineering, Nanyang Technology University

50 Nanyang Avenue, Singapore 639798, Tel: (65) 6790 5294; Fax: (65) 6792 1650

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

 

DOI:10.18057/IJASC.2008.4.2.5

 

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ABSTRACT

  This paper presents the experimental studies of two partially overlapped CHS   K-joints specimens (Specimens S1 and S2) with through brace subjected to basic and combined loads. The stress analysis of the joints revealed the maximum stress concentration factor (SCF) to be located on the brace side. Then, the maximum SCF was compared with existing Efthymiou’s formulae. It is observed that the Efthymiou’s formulae are over-conservative in in-plane bending load case (IPB), but in axial load case (AX) are not conservative. In addition, the fatigue life was also compared with existing S-N curves. The S-N curve was found to be marginally conservative for first specimen, but it was not conservative for other one.

 

KEYWORDS

Partially overlapped K-joints, stress concentration and stress intensity factor, fatigue failure, surface and through-thickness cracks

 


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