References

A.4.1 Peterson, R. E: 'Stress concentration factors1 John Wiley and Sons Inc., 1974.

A.4.2 Roark, J. R. and Young, W. C: 'Formulas for stress and strain1, McGraw Hill, 1973.

A.43 Niemi, E.: 'Stress determination for fatigue analysis of welded components1, (International Institute of

Welding document 1221-93), Abington Publishing, Cambridge, 1995. A.4.4 BS7608 'Code of practice for fatigue design and assessment of steel structures',British Standards Institute 1993.

A.4.5 Hobbacher, A: 'Recommendations on fatigue of welded components', IIW Doc. XIII-1539-94/XV-845/-94.

Stress Based Fatigue Analysis And Design
B

a) Fatigue stress concentration factor for unreinforced apertures based on net stress at X

Stress Concentration Factor
FigA.2.1. Typical stress concentration factors from radiused corners in flat plate

Load applied in the brace Crown point

Load applied in the brace Crown point

Crown Point Saddle Point Weld

Brace

Saddle point

Chord a) Nodal joint nomenclature

Brace

Saddle point

Chord a) Nodal joint nomenclature

Increase in stress due to overall joint geometry

Stress in brace

Extrapolation of geometric stress distribution to weld toe

Chord wall

Stress increase due to weld geometry

Increase in stress due to overall joint geometry

Stress in brace

Extrapolation of geometric stress distribution to weld toe

Geometric Stress

Nominal stress

Brace wall Weld toe Weld

Brace hot spot stress = nominal stress x SCFbrace

Nominal stress

Brace wall Weld toe Weld

Brace hot spot stress = nominal stress x SCFbrace b) Stress distribution in brace

Extrapolation of geometric stress distribution to weld toe

Increase in stress due to overall joint geometry

Extrapolation of geometric stress distribution to weld toe

Increase in stress due to overall joint geometry

Hot Spot Stress For Fem Analysis

-f" Stress increase due to weld geometry

Brace wall

Weld toe Weld

Chord hot spot stress = nominal stress x SCF^

c) Stress distribution in chord

Fig.A.3.1 Example of hot spot stresses in a tubular lattice joint

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