Skip to main content
Log in

A study of fatigue crack propagation at a web stiffener on a longitudinal stiffener

  • Original Article
  • Published:
Journal of Marine Science and Technology Aims and scope Submit manuscript

Abstract

Predicting fatigue crack growth after its detection during in-service inspection is necessary to prevent a loss of serviceability, such as the oil and/or water tightness of critical compartments. This paper focuses on the most typical fatigue cracks that start at the weld joint between a flat bar stiffener on a transverse web frame and the flange of a longitudinal stiffener on a bottom plate or inner bottom plate. An experiment is carried out to observe the fatigue crack propagation for two kinds of flat bars at the abovementioned connection. The experimental results, especially the surface crack growth on the flange (which dominates during the total fatigue life of the longitudinal stiffener), are compared with crack growth curves predicted using a few existing formulas. Based on the comparative study, a formula that shows the best agreement with the experiment results is selected. Weld toe magnification factors for the web stiffener are computed from the crack propagation rates measured in the experiment, and two equations for the magnification factors versus crack depth are developed for two types of web stiffeners. The selected existing formula and the proposed equations are applied to two connections at the inner bottom and side longitudinal bulkhead of an LNG carrier. The equivalent stress approach based on a long-term distribution is employed to avoid the complexity involved in dealing with the actual stress history. Using this prediction, the remaining service life until an oil or water leakage occurs at a tank boundary can be estimated when a fatigue crack at the connection is detected.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19
Fig. 20
Fig. 21

Similar content being viewed by others

References

  1. Mizukami T, Ishikawa I, Yuasa M (1994) Trends of recent hull damage and countermeasures. Class NK Tech Bull 12:25–45

    Google Scholar 

  2. Okamoto T, Toyosada M (1979) Fatigue crack initiation and propagation at a bracket end weld toe. J Kansai Soc Nav Archit 175:31–41

    Google Scholar 

  3. Kataza T, Murata S, Tateishi M, Toyosada M, Okamoto T, Fujiwara H, Miwa S, Kanazawa T (1981) A proposal of fracture control design procedure. J Soc Nav Archit Jpn 149:174–194

    Google Scholar 

  4. Sumi Y, Chen Y, Hayashi S (1996) Morphological aspects of fatigue crack propagation, part I—computational procedure. Int J Fract 82:205–220

    Article  Google Scholar 

  5. Sumi Y, Chen Y, Wang ZN (1996) Morphological aspects of fatigue crack propagation, part II—effects of stress biaxiality and welding residual stress. Int J Fract 82(3):221–235

    Article  Google Scholar 

  6. Sumi Y (1998) Fatigue crack propagation and computational remaining life assessment of ship structures. J Mar Sci Technol 3(2):102–112

    Article  MathSciNet  Google Scholar 

  7. Sumi Y, Mohri M, Kawamura Y (2004) Computational prediction of fatigue crack paths in ship structural details. Fatigue Fract Eng Mater Struct 28(1–2):107–115

    Google Scholar 

  8. Sumi Y, Mohri M (2004) Simulation-based fatigue crack management for ship structural details. In: Proc 9th Symp on Practical Design of Ships and Other Floating Structures, Luebeek-Travemuende, Germany, 12- 17 Sept 2004

  9. Chun YC, Kim YI, Kang JK, Han JM (2001) A study on fatigue life prediction of welded joints through fatigue test and crack propagation analysis. J Soc Nav Archit Korea 38(3):99–106

    Google Scholar 

  10. Det Norske Veritas (2005) Fatigue strength analysis of offshore steel structures (RP-203). Det Norske Veritas, Hovik

  11. Verreman Y, Baïlon JP, Masounave J (1987) Fatigue life prediction of welded joints—a re-assessment. Fatigue Fract Eng Mater Struct 10(1):17–36

    Article  Google Scholar 

  12. Matsuoka K, Fujii E (1995) An evaluation method on fatigue crack initiation life at welded joints in steel structures. J Soc Nav Archit Jpn 178:513–522

    Google Scholar 

  13. Det Norske Veritas (2003) Fatigue assessment of ship structures (Classification Notes, No. 30.7). Det Norske Veritas, Hovik

  14. British Standards Institution (1980) BS 5400: Pt 10: Specification for steel, concrete and composite bridges. In: Code of practice for fatigue. British Standards Institution, London

  15. Newman JC, Raju IS (1981) An empirical stress–intensity factor equation for the surface crack. Eng Fract Mech 15:185–192

    Google Scholar 

  16. Newman JC, Raju IS (1979) Stress-intensity factors for a wide range of semi-elliptical surface cracks in finite-thickness plates. Eng Fract Mech 11:817–829

    Article  Google Scholar 

  17. Maddox SJ (1975) An analysis of fatigue cracks in fillet welded joints. Int J Fract 11:221–243

    Article  Google Scholar 

  18. Wang X, Lambert SB (1998) Weight functions and stress intensity factors for semi-elliptical cracks in T-plate welded joints. Fatigue Fract Eng Mater Struct 21:99–117

    Article  Google Scholar 

  19. Bowness D, Lee MK (1996) Stress intensity factor solutions for semi-elliptical weld toe cracks in T-butt geometries. Fatigue Fract Eng Mater Struct 19(6):787–797

    Article  Google Scholar 

  20. Elber W (1971) The significance of fatigue crack closure, damage tolerance in aircraft structures (ASTM STP 486). American Society for Testing and Materials, Philadelphia, pp 230–242

  21. Lu YL (1995) A practical procedure for evaluating SIFs along fronts of semi-elliptical surface cracks at weld toes in complex stress fields. Int J Fatigue 18(2):127–135

    Article  Google Scholar 

  22. Foroughi R, Radon JC (1988) Crack closure behavior of surface cracks under pure bending. In: Newman JC Jr, Elber W (eds) Mechanics of fatigue crack closure (ASTM STP 982). American Society for Testing and Materials, Philadelphia, pp 260–269

  23. Kang SW, Han SH, Kim WS, Paik YM (2003) Fatigue strength of fillet weldment under out-of-plane bending load. J Soc Nav Archit Korea 40(1):28–35

    Google Scholar 

  24. Kawahara M, Kurihara M (1975) A preliminary study on surface crack growth in a combined tensile and bending fatigue process. J Soc Nav Archit Jpn 137:297–306

    Google Scholar 

  25. American Bureau of Shipping (2006) Guide notes on spectral-based fatigue analysis for floating offshore structures. American Bureau of Shipping, Houston

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Beom-Seon Jang.

About this article

Cite this article

Jang, BS., Ito, H., Kim, KS. et al. A study of fatigue crack propagation at a web stiffener on a longitudinal stiffener. J Mar Sci Technol 15, 176–189 (2010). https://doi.org/10.1007/s00773-009-0082-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00773-009-0082-1

Keywords

Navigation