Analysis on the Fatigue Crack Propagation of Weld Toe Crack through Residual Stress Field

잔류응력장을 전파하는 용접 토우부 균열의 전파해석

  • 김유일 (대우중공업 선박해양기술연구소) ;
  • 전유철 (대우중공업 선박해양기술연구소) ;
  • 강중규 (대우중공업 선박해양기술연구소) ;
  • 한종만 (대우중공업 선박해양기술연구소) ;
  • 한민구 (거제대학 기계과)
  • Published : 2000.10.01

Abstract

Fatigue crack propagation life of weld toe crack through residual stress field was estimated with Elber's crack concept. Propagation of weld toe crack is heavily influenced by residual stress caused by welding process, so it is essential to take into account the effect of residual stress on the propagation life of weld toe crack. Fatigue crack at transverse and longitudinal weld toe was studied respectively, which represent typical weld joint in ship structure. Numerical and experimental studies are performed for both cases. Residual stress near weldment was estimated through nonlinear thermo-elasto-plastic finite element method, and residual stress intensity factor with Glinka's weight function method. Effective stress intensity factor was calculated with Newman-Forman-de Koning-Henriksen equation which is based on Dugdale strip yield model in estimating crack closure level U at different stress ratio. Calculated crack propagation life coincided well with experimental results.

Keywords

References

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