Fatigue design of welded aluminum rectangular hollow section joints

Macdonald, Kenneth A.; Haagensen, P.J.

doi:10.1016/s1350-6307(98)00025-9

Cited by 18 publications

(8 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Dealing with fatigue strength, Eurocode 3 suggests for welded details a scaling law with an exponent 0.25, to be used when the main plate thickness is greater than 25 mm. Assessment of very recent research data has indicated an influence of thickness stronger than that suggested so the exponent was increased to 0.30 in the latest HSE and API/ISO revision for offshore structures 34 . It is important to note that in the presence of an opening angle between the weld flank and main plate equal to 135 degrees, to be considered the more typical value, 1– λ 1 in Eq.…”

Section: Some Simple Remarks On the Scale Effect Under Fatigue Loadingmentioning

confidence: 97%

“…Assessment of very recent research data has indicated an influence of thickness stronger than that suggested so the exponent was increased to 0.30 in the latest HSE and API/ISO revision for offshore structures. 34 It is important to note that in the presence of an opening angle between the weld flank and main plate equal to 135 degrees, to be considered the more typical value, 1±l 1 in Eq. (30) is 0.326 and Eq.…”

Section: Plastic Contributionmentioning

confidence: 99%

See 1 more Smart Citation

The Equivalent Strain Energy Density approach re‐formulated and applied to sharp V‐shaped notches under localized and generalized plasticity

Lazzarin

Zambardi

2002

Fatigue Fract Eng Mat Struct

105

View full text Add to dashboard Cite

In the case of a rounded notch, the stress and strain at the notch tip can be determined by the traditional Neuber rule or by the Equivalent Strain Energy Density (ESED) approach, as formulated by Glinka and Molski. In the latter case the elastoplastic strain energy density at the notch tip is thought of as coincident with that determined under purely elastic conditions. For sharply V-shaped notches this approach is not directly applicable, since the strain energy density at the notch tip tends toward infinity both for a material obeying an elastic law and a material obeying a power hardening law. By using the notch stress intensity factors, the present paper suggests a re-formulation of the ESED approach which is applied no longer at the notch tip but to a finite size circular sector surrounding the notch tip. In particular we have adopted the hypothesis that, under plane strain conditions, the value of the energy concentration due to the notch is constant and independent of the two constitutive laws. When small scale yielding conditions are present, such a hypothesis immediately results in the constancy of the strain energy averaged over the process volume. As a consequence, plastic notch stress intensity factors valid for sharp V-shaped notches can be predicted on the basis of the linear elastic stress distributions alone

show abstract

Section: Some Simple Remarks On the Scale Effect Under Fatigue Loadingmentioning

confidence: 97%

Section: Plastic Contributionmentioning

confidence: 99%

The Equivalent Strain Energy Density approach re‐formulated and applied to sharp V‐shaped notches under localized and generalized plasticity

Lazzarin

Zambardi

2002

Fatigue Fract Eng Mat Struct

105

View full text Add to dashboard Cite

show abstract

“…The former value confirms the prevailing role played by the nucleation and early propagation phases on the total fatigue life of the welded details analysed here. Dealing with scale effect, Macdonald and Haagensen (1999) emphasised the fact that assessment of recent research data had indicated an influence of thickness stronger than that suggested by Eurocode 3 (where the exponent is 0.25), so that, they wrote, in the latest HSE and API/ISO revision for offshore structures a higher penalty factor of 0.30 was imposed. By using the scatter bands curves already shown reported in Figures 3 and 4 (which also include fatigue data obtained from AISI 304L and Duplex 2205) one can obtained some simplified rules to be applied at 5 million cycles by considering two different levels of probability of survival.…”

Section: Fatigue Strength Of Steel and Aluminium 261mentioning

confidence: 99%

Fatigue strength of steel and aluminium welded joints based on generalised stress intensity factors and local strain energy values

2005

View full text Add to dashboard Cite

Weld bead geometry cannot, by its nature, be precisely defined. Parameters such as bead shape and toe radius vary from joint to joint even in well-controlled manufacturing operations. In the present paper the weld toe region is modelled as a sharp, zero radius, V-shaped notch and the intensity of asymptotic stress distributions obeying Williams' solution are quantified by means of the Notch Stress Intensity Factors (NSIFs). When the constancy of the angle included between weld flanks and main plates is assured and the angle is large enough to make mode II contribution non-singular, mode I NSIF can be directly used to summarise the fatigue strength of welded joints having very different geometry. By using a large amount of experimental data taken from the literature and related to a V-notch angle of 135 degrees, two NSIF-based bands are reported for steel and aluminium welded joints under a nominal load ratio about equal to zero. A third band is reported for steel welded joints with failures originated from the weld roots, where the lack of penetration zone is treated as a crack-like notch and units for NSIFs are the same as conventional SIF used in LEFM. Afterwards, in order to overcome the problem related to the variability of the V-notch opening angle, the synthesis is made by simply using a scalar quantity, i.e. the mean value of the strain energy averaged in the structural volume surrounding the notch tips. This energy is given in closed form on the basis of the relevant NSIFs for modes I and II and the radius R-c of the averaging zone is carefully identified with reference to conventional arc welding processes. Rc for welded joints made of steel and aluminium considered here is 0.28mm and 0.12mm, respectively Different values of Rc might characterise welded joints obtained from high-power processes, in particular from automated laser beam welding. The local-energy based criterion is applied to steel welded joints under prevailing mode I (with failures both at the weld root and toe) and to aluminium welded joints under mode I and mixed load modes (with mode II contribution prevailing on that ascribable to mode I). Surprising, the mean value of Delta W related to the two groups of welded materials was found practically coincident at 2 million cycles. More than 750 fatigue data have been considered in the analyses reported herein

show abstract

“…4. Analysed geometries of aluminium welded joints subjected to multiaxial loads and FE analyses according to the PSM Various experimental data available in literature, dealing with weld toe and weld root fatigue failures in aluminium alloys welded joints subjected to both uniaxial and multiaxial fatigue loading [45][46][47][48][49][50][51] have been re-analysed according to the PSM. The considered joint geometries and relevant loading conditions are reported in table 3.…”

Section: Automated Implementation Of the Psm In Ansys ® Mechanicalmentioning

confidence: 99%

Implementation of the Peak Stress Method for the automated FEA-assisted design of aluminium welded joints subjected to constant amplitude multiaxial fatigue loads

Visentin

Campagnolo

Simonaggio

et al. 2023

IOP Conf. Ser.: Mater. Sci. Eng.

View full text Add to dashboard Cite

The Peak Stress Method (PSM) is a FE-oriented local approach to the fatigue strength assessment of welded structures subjected to fatigue loading. Starting from the peak stresses calculated at the V-notch tip nodes defining weld toes or the weld roots, the PSM defines an equivalent peak stress which allows to estimate the fatigue failure location and fatigue lifetime of welded structures, in compliance with appropriate fatigue design curves. An Ansys® Mechanical extension has been developed to achieve full automated implementation of the tasks and calculations necessary to apply the PSM to welded structures. The tool allows to identify and analyse all the V-notch tip edges of the structure and perform fatigue life estimation on each analysed node. As an output, fatigue life results can be visualized through dedicated tabular data, graphs and contour results generated over the edges of the model. In this work, common-to-complex 3D geometries taken from the literature and related to aluminium alloys welded joints subjected to uniaxial as well as multiaxial fatigue loads have been analysed by comparing two design approaches: (i) manual application of the PSM, (ii) automated implementation of the PSM. The tool developed in Ansys® Mechanical allows to significantly contain the time and effort required to analyse welded structures according to the PSM.

show abstract

Fatigue design of welded aluminum rectangular hollow section joints

Cited by 18 publications

References 7 publications

The Equivalent Strain Energy Density approach re‐formulated and applied to sharp V‐shaped notches under localized and generalized plasticity

The Equivalent Strain Energy Density approach re‐formulated and applied to sharp V‐shaped notches under localized and generalized plasticity

Fatigue strength of steel and aluminium welded joints based on generalised stress intensity factors and local strain energy values

Implementation of the Peak Stress Method for the automated FEA-assisted design of aluminium welded joints subjected to constant amplitude multiaxial fatigue loads

Contact Info

Product

Resources

About