Abstract
The weld magnification factor method has been widely used in the determination of the stress intensity factor (SIF) for weld-toe cracks in welded structural components. Weld magnification factors M kare normally derived from two-dimensional crack models with fillet weld profiles to take account of the effect of weld-notch stress concentration at the deepest point of the crack front. This paper presents a detailed three-dimensional analysis of weld-toe surface cracks in fillet welded T-butt joint models using the finite element method. Effects of the weld notch and the welded attachment stiffness on the SIFs of the weld-toe surface cracks have been studied quantitatively. Weld magnification factors applying to the whole surface crack fronts have been estimated. Numerical results show two contradictory effects; that the effect of weld notch increases SIF values throughout the shallow surface crack fronts which are in the region of notch stress concentration, while the effect of local structural constraint reduces the SIF values. The increase in the SIF values mainly depends upon the relative crack front depth and the decrease in the SIF values mainly depends upon the crack shape aspect ratio for a specific weld profile. Both effects on the weld magnification factors can be estimated separately. A simple approach for deriving the weld magnification factors for various weld-toe surface crack problems is proposed for engineering applications.
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References
S.J. Maddox, International Journal of Fracture 11, (1975) 221–243.
British Standard Published Document PD 6493, Method for the Derivation of Acceptance Levels for Flaw in Fusion Welded Joints, British Standard Institution, UK (1991).
I.J. Smith and S.J. Hurworth, The Effect of Geometry Changes upon the Predicted Fatigue Predicted Fatigue Strength of Welded Joints, TWI Report 244/1984, The Welding Institute, Cambridge, UK (1984).
X. Niu and G. Glinka, International Journal of Fracture 35 (1987) 3–20.
S.D. Thurlbeck and F.M. Burdekin, Effects of Geometry and Loading Variables on the Fatigue Design Curve for Tubular Joints, IIW Document XIII-1428–91, International Institution of Welding (1991).
I.J. van Straalen, O.D. Dijkstra and H.H. Snijder, in Proceedings of the International Conference on Weld Failures (London) (1988) 367–376.
O.D. Dijkstra, H.H. Snijder and I.J. van Straalen, in Proceedings of 8th International Conference on Offshore Mechanics and Arctic Engineering (Hague) (1989) III.137–143.
R. Bell, Stress Intensity Factors for Weld Toe Cracks in Welded T Plate Joints, DSS Contract No. OST84–00125, Faculty of Engineering, Carleton University, Ottawa (1987).
B. Fu, J.V. Haswell and P. Bettess, in Proceedings of the 1st International Conference on Shallow Crack Fracture Mechanics Toughness Tests and Applications, The Welding Institute (Cambridge) (1992) Paper 22.
J.C. Newman and I.S. Raju, Engineering Fracture Mechanics 15 (1981) 185–192.
H.L.J. Pang, A. Review of Stress Intensity Factors for Semi-Elliptical Surface Cracks in a Plate and Fillet Welded Joint, TWI Report 426/1990, The Welding Institute, Cambridge, UK (1990).
J.C. NewmanJr and I.S. Raju, Stress Intensity Factor Equations for Cracks in Three Dimensional Finite Bodies Subjected to Tension and Bending Loads, NASA-TM-85793, NASA Langley Research Center, Virginia, USA (1984).
R.S. Barsoum, International Journal on Numerical Methods for Engineering 10 (1976) 25–27.
ABAQUS Users Manual (Version 4.8), Hibbitt, Karlsson and Sorensen Inc, Providence, USA (1989).
D.M. Parks, Computer Methods in Applied Mechanics and Engineering 12 (1977) 353–364.
B. Fu, Variations in Stress Singularity of Surface Cracks and the Effect in Determination of Stress intensity Factor Solutions, ERS R4909, Engineering Research Station, British Gas plc., Newcastle upon Tyne, UK (1992).
I.S. Raju and J.C. NewmanJr, Engineering Fracture Mechanics 11 (1979) 817–829.
RS/1 Users Guide, BBN Software Production Corporation, Cambridge, USA (1988).
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Fu, B., Haswell, J.V. & Bettess, P. Weld magnification factors for semi-elliptical surface cracks in fillet welded T-butt joint models. Int J Fract 63, 155–171 (1993). https://doi.org/10.1007/BF00017283
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DOI: https://doi.org/10.1007/BF00017283