Elastic-Plastic Fracture Mechanics Analysis of Off-Centred Circumferential Through-Wall Cracked Pipes

비대칭 원주방향 관통균열 배관의 탄소성 파괴역학해석

  • 심도준 (성균관대학교 기계공학부) ;
  • 허남수 (성균관대학교 기계공학부) ;
  • 김윤재 (성균관대학교 기계공학부) ;
  • 김영진 (성균관대학교 기계공학부)
  • Published : 2003.04.23

Abstract

This paper provides approximate J estimates for off-centred, circumferential through-wall cracks in cylinders under bending. The proposed method is based on the reference stress approach, where the dependence of elastic and plastic influence functions of J on the cylinder/crack geometry, the off-centred angle and strain hardening is minimised through the use of a proper normalising load. Based on published limited FE results for off-centred, circumferential through-wall cracks under bending, such normalising load is found, based on which the reference stress based J estimates are proposed for more general cases, such as for a different cylinder geometry. Comparison of the estimated J with extensive FE J results shows overall good agreements for different crack/cylinder geometries which provides sufficient confidence in the use of the proposed method to fracture mechanics analyses of off-centred circumferential cracks. Furthermore, the proposed method is simple to use, giving significant merits in practice.

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