Ocean Systems Engineering

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Stress concentration factors in tubular T-joints stiffened with external ring under axial load

  • Hossein Nassiraei (Department of Civil Engineering, Faculty of Engineering, University of Guilan) ;
  • Pooya Rezadoost (Faculty of Civil Engineering, K.N. Toosi University of Technology)
  • Received : 2023.01.03
  • Accepted : 2023.03.14
  • Published : 2023.03.25
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Abstract

In this study, the SCFs in tubular T-joints stiffened with external ring under axial load are studied and discussed. After verification of the present numerical model with the results of several available experimental tests, 156 FE models were generated and analyzed to parametrically evaluate the effect of the joint geometry and the ring geometry on the SCFs. Results indicated that the SCF of the stiffened T-joints at crown point can be down to 24% of the SCF of the corresponding un-reinforced joint at the same point. Also, the effect of the ring on the SCF at saddle point is more remarkable than the effect of the ring on the SCF at crown point. Moreover, against un-reinforced joints under axial load, the SCF at saddle point of the stiffened joint is smaller than the SCF at crown point of that stiffened joint. The ring results in the redistribution of stresses in the ring and metal substrate. Also, the effect of the ring thickness on the decrease of the SCFs is slight and can be ignored. In final step, the geometric parameters affecting the SCFs of the stiffened T-joints are analyzed by multiple nonlinear regression analyses. An accurate formula is proposed for determining the SCFs.

Keywords

Acknowledgement

The authors gratefully acknowledge the useful comments of anonymous reviewers on the draft version of this paper.

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