대한기계학회논문집A (Transactions of the Korean Society of Mechanical Engineers A)

  • 제28권10호
  • /
  • Pages.1549-1557
  • /
  • 2004
  • /
  • 1226-4873(pISSN)
  • /
  • 2288-5226(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
권호 표지
DOI QR코드

DOI QR Code

십자형 필렛용접 이음부의 복수균열 진전수명 평가

Fatigue Life Estimation of Cruciform Welded Joint Considering Multiple Collinear Surface Cracks

  • 한승호 (한국기계연구원 구조연구부) ;
  • 신병천 (한국기계연구원 구조연구부) ;
  • 김재훈 (충남대학교 기계설계공학과) ;
  • 한정우 (한국기계연구원 구조연구부)
  • 발행 : 2004.10.01
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

Fatigue life of welded joints is governed by the propagation of multiple collinear surface cracks distributed randomly along weld toe. These cracks propagate under the mechanisms of mutual interaction and coalescence of the adjacent two cracks. To estimate the fatigue life, its influences on the above two mechanisms should be taken into account, which appear through the stress intensity factors disturbed mutually. However, it is difficult to calculate the stress intensity factors of the multiple surface cracks located in vicinity of weld toe due to its geometrical complexity. They are calculated normally by using the Μk-factors, but such Mk-factors are very rare in literature. In this study, the Μ$textsc{k}$-factors were obtained from a parametric study on crack length and depth, for which a finite element method is used. A fatigue test for a cruciform welded Joint was conducted and the fatigue life of the tested specimen was estimated using the present method with the informations obtained from the test, such as the number, size, and locations of the cracks. The estimated and measured fatigue life showed a good agreement.

키워드

참고문헌

  1. Lee, J., Chio, Y. and Kim, Y., 1993, 'Fatigue Growth Life Prediction for Collinear Multiple Surface Cracks,' Transactions of KSME, Vol. 17, No. 5, pp. 1668-1677
  2. Suh, C, Hwang, N. and Park, M., 1994, 'Fatigue Crack Growth, Coalescence Behavior and Its Simulation on Multi-surface Cracks,' Transactions of KSME, Vol. 18, No. 3, pp. 716-728
  3. Kim, J., Lee, J. and Hong, C, 1996, 'Fatigue Life Prediction for Multiple Surface Cracks in Finite Plates,' Transactions of the Society of Naval Architecture of Korea, Vol. 33, No. 4, pp. 75-86
  4. Yamada, K., Makino, T., Baba, C. and Kikuchi Y., 1980, 'Fatigue Analysis Based on Crack Growth from Toe of Gusset End Weld,' Journal of JSCE, Vol. 303, pp. 31-41
  5. Yamada, K., Makino, T. and Kikuchi Y., 1979, 'Fracture Mechanics Analysis of Fatigue Cracks Emanating from Toe of Fillet Weld,' Journal of JSCE, Vol. 292, pp. 1-12
  6. Madox, S., 1975, 'An Analysis of Fatigue Cracks in Fillet Welded Joints,' International Journal of Fracture, Vol. 11, No. 2 pp. 221-243 https://doi.org/10.1007/BF00038890
  7. Bowness, D and Lee, M., 2000, 'Prediction of Weld Toe Magnification Factors for Semi-elliptical Cracks in T-butt joints,' International Journal of Fatigue, Vol. 22, pp. 369-387 https://doi.org/10.1016/S0142-1123(00)00012-8
  8. Newman, J. and Raju, I., 1981, 'An Empirical Stress Intensity Factor Equation for the Surface Crack,' Engineering Fracture Mechanics, Vol. 15, No. 1-2, pp. 185-192 https://doi.org/10.1016/0013-7944(81)90116-8
  9. Fett, T., 1987, 'An Extension of the Newman-Raju Formula,' International Journal of Fracture, Vol. 33, pp. R47-R50 https://doi.org/10.1007/BF00013174
  10. Murakami, Y. and Nisitani, H., 1981, 'Stress Intensity Factor for Interacting Two Equal Semi-Elliptical Surface Cracks in Tension,' JSME Ser. A, Vol. 50, pp. 295-303
  11. Nemat-Nasser, S., 1982, 'Interacting Dissimilar Semi-Elliptical Surface Flaws under Tension and Bending,' Engng. Frac. Mech., Vol. 16, pp. 373-386 https://doi.org/10.1016/0013-7944(82)90115-1
  12. Yuuki, R. and Yoshida, T., 1986, 'Fatigue Life Prediction System for Structures,' Journal of High Pressure Institute, Vol. 24, No. 3, pp. 115-123
  13. ASME, 1989, 'Boiler and Pressure Vessel Code, Sec. XI : Rules for In-service Inspection of Nuclear Power Plant Components
  14. British Standard Institute, 1980, 'Guidance on Some Methods for the Deviations of Acceptance Levels for Defects in Fusion Welded Joints' PD 6493
  15. BS 7910:1999, 'Guide on Methods for Assessing the Acceptability of Flaws in Metallic Structures,' British Standard
  16. Han, J., Han, S., Shin, B. and Kim, J., 2003, 'Fatigue Life Evaluation Based on Welding Residual Stress Relaxation and Notch Strain Approach for Cruciform Welded Joint,' Proceedings of the KSME 2003 Fall Annual Meeting, pp. 1103-1108