Vol. 10, No. 4, pp. 476-497 (2014)
NUMERICAL ANALYSIS OF FATIGUE BEHAVIOR OF WELDED CFCHS T-JOINTS
Min Gu1, Le-Wei Tong2,*, Xiao-Ling Zhao3 and Yun-Feng Zhang4
1,2State key laboratory for Disaster Reduction in Civil Engineering, Tongji University
and College of Civil Engineering, Tongji University, Shanghai 200092, China
3Department of Civil Engineering, Monash University, Clayton, VIC 3800, Australia
4Department of Civil & Environmental Engineering, University of Maryland,
College Park, MD 20742, USA and Guang-Hua Education Foundation Scholar, College of Civil Engineering,Tongji University, Shanghai 200092, China
*(Corresponding author: E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it. )
Received: 21 February 2014; Revised: 29 April 2014; Accepted: 2 May 2014
DOI:10.18057/IJASC.2014.10.4.7
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ABSTRACT
Fatigue life assessment of welded joints made of circular hollo w sections (CHS) with concrete filled (CF) chord member subject to vehicle load is vital in designing of CFCHS arch truss bridge. A key issue in fatigue life assessment of such joints is how to accurately estimate the stress intensity factor. This paper describes a methodology for calculating the stress intensity factor of the hot spot region in the welded CFCHS T-joints based on a finite element analysis which considers weld modeling, crack modeling and nonlinear interface element between steel and concrete. A procedure for fatigue life estimation of welded CFCHS T-joints is also established. Discussions are made on the effect of the initial crack size and concrete strength on fatigue life and hot spot stresses. The majority of crack propagation life is found to be associated with the shallow crack stage. The proposed method gives reasonable estimation of fatigue life of welded CFCHS T-joints.
KEYWORDS
Concrete-filled circular hollow section, Welded joints, Fatigue life prediction, Fracture mechanics, Finite element analysis
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