A method to estimate plastic loads for elbows with non-uniform thicknesses

Yun Jae Kim, N. H. Kim, C. Y. Oh, C. S. Oh

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

This paper provides a method to estimate plastic loads [defined by the twice-elastic-slope (TES)]for elbows with non-uniform thicknesses under in-plane bending and under internal pressure, based on systematic FE limit analyses using elastic-perfectly plastic materials. The intrados thickness is assumed to be up to 30% thicker than the straight pipe thickness, whereas the extrados thickness up to 30% thinner. The FE plastic loads are compared with estimated ones using closed-form approximations for elbows with uniform thicknesses, to provide guidance on the choice of a representative thickness to predict plastic loads for elbows with non-uniform thicknesses. Results suggest that the use of the straight pipe thickness gives overall satisfactory predictions. Estimated plastic loads are conservative, and differ from FE results by less than 10% for all cases considered. Despite its simplicity, results look very promising, and thus the use of the straight pipe thickness can be recommended to estimate plastic loads for elbows with non-uniform thicknesses in practice.

Original languageEnglish
Pages (from-to)822-837
Number of pages16
JournalFatigue and Fracture of Engineering Materials and Structures
Volume31
Issue number9
DOIs
Publication statusPublished - 2008 Oct 30
Externally publishedYes

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Keywords

  • Elbow
  • Finite-element limit analysis
  • Non-uniform thickness
  • Plastic load
  • Twice-elastic-slope

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

A method to estimate plastic loads for elbows with non-uniform thicknesses. / Kim, Yun Jae; Kim, N. H.; Oh, C. Y.; Oh, C. S.

In: Fatigue and Fracture of Engineering Materials and Structures, Vol. 31, No. 9, 30.10.2008, p. 822-837.

Research output: Contribution to journalArticle

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