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Eurocode 3

List of Classification Parameters

Evaluation Distance
Reference distance to find the evaluation location from the weld element at which the stress values are extracted.
Weld Width
Width of the weld material from the web wall. This parameter is ignored if specifying the evaluation distance is done manually.
Note: Refer to - Find Evaluation Positions.
Safety Factor (Gmf)
Used in calculation of the corrected weld detail category.
Fatigue Limit Slope - Normal Stress (Md)
Slope of the curve at the fatigue limit for normal stress components of tensor. Refer to location 2 in the graph.
Fatigue Limit Slope - Shear Stress (Md)
Slope of the curve at the fatigue limit for shear stress components of tensor. Refer to location 2 in the graph.
Cutoff Limit Slope - Normal Stress (Ml)
Slope of the curve at the cutoff limit for normal stress components of tensor. Refer to location 3 in the graph.
Cutoff Limit Slope - Shear Stress (Ml)
Slope of the curve at the cutoff limit for shear stress components of tensor. Refer to location 3 in the graph.
Number of Cycles at Fatigue Limit (Nd)
Number of cycles in the S-N curve at the fatigue limit.
Number of Cycles at Cutoff Limit (Nd)
Number of cycles in the S-N curve at the cutoff limit.
Desired Cycles Detail From
Parameter that will show where HL-WC is reading the desired number of cycles from.

Location Wise Parameters

Note: Where ‘X’ in the below parameters can be any evaluation location from 1-10.
Weld Detail Category - Transverse Location_X
Weld detail category from the image below that will be considered for the calculation of fatigue and cutoff limits of the normal stress component in the transverse direction (perpendicular to the axis of the weld) at ‘X’.
Weld Detail Category - Longitudinal Location_X
Weld detail category from the image below that will be considered for the calculation of fatigue and cutoff limits of the normal stress component in the longitudinal direction (parallel to the axis of the weld) at ‘X’.
Weld Detail Category - Shear Location_X
Weld detail category from the image below that will be considered for the calculation of fatigue and cutoff limits of the shear stress component at ‘X’.
Material Yield - Location_X
Material yield value used for the static evaluation.


Figure 1.

Symbols

  • Weld detail category (Normal) - Δσc
  • Weld detail category (Shear) - Δτc
  • Safety factor for strength - γMf

Static Assessment

The following process is followed for Static assessment:
  1. Retrieve the six components of stress from the element at the evaluation location.
  2. Calculate the von Mises stress value using these stress components.
  3. Retrieve the material yield value from the Points context.
  4. Determine the static strength ratio: element von Mises stress / material yield value

Formulation

Stress Component Considered for Evaluation
ΔσT - Transverse component (perpendicular to the axis of the weld)
ΔσL - Longitudinal component (parallel to the axis of the weld)
Δτ - Shear component
Corrected Weld Detail Category
Δσc(Corrected)=Δσc,BasicγMf
Where:
  • Δσc,Basic - Weld detail category before correction.
Note: The above formulas are for the normal component. Similar formulas are applicable to other shear components as well.
Calculation of the Assessment Stress
In the case of Eurocode, stress range is used as assessment stress.
Δσ(StressRange)=(σmaxσmin)
Fatigue Limit Calculation (ΔσD)
For Normal Component: ΔσD=Δσc·(2,0e+6ND)(1/mD)
For Shear Component: ΔσD=
Where:
  • Δσc - Corrected stress range value
  • ND - Number of cycles at fatigue limit
  • mD - Slope at fatigue limit
Cutoff Limit Calculation (ΔσL)
For Normal Component: ΔσL=ΔσD·(NDNL)(1/mL)
For Shear Component: ΔσL=Δσc·(2,0e+6NL)(1/mL)
Where:
  • Δσc - Corrected stress range value
  • ΔσD - Fatigue limit stress value
  • ND - Number of cycles at fatigue limit
  • NL - Number of cycles at cutoff limit
  • mL - Slope at cutoff limit
Permissible Number of Cycles (Nperm)
If ΔσΔσDNperm=ND·(ΔσΔσD)(mD)If ΔσD>ΔσΔσLNperm=NL·(ΔσΔσL)(mL)If Δσ<ΔσLNperm=
Damage Calculation
D=NNperm
Where:
  • N - Desired number of cycles per load case combination, derived either from the range data file or the classification area.
Resultant Damage Calculation (D)
D=12·(|Dδ,x+Dδ,y|+(Dδ,xDδ,y)2+4·Dτ,xy2)<1.0
Where:
  • Dδ,x - Damage in longitudinal direction (parallel to the axis of the weld)
  • Dδ,y - Damage in transverse direction (perpendicular to the axis of the weld)
  • Dτ,xy - Damage in the shear direction
Calculation of Accumulated Damage
For the corresponding damage components:

Dδ,x,acc=Dx,iDδ,y,acc=Dy,iDτ,xy,acc=Dxy,i

For resultant accumulated damage calculation:

Dacc=12·(|Dδ,x,acc+Dδ,y,acc|+(Dδ,x,accDδ,y.acc)2+4·Dτ,xy,acc2)<1.0

Note: DIN is the copyright owner for EN 1999-1-3:2011-11 (November 2011). Permission to use and reproduce information contained in the Eurocode 3 standards was granted by DIN.