Apply Global Fatigue Solution Settings

Apply fatigue solution settings to the entire assembly.

Global default fatigue solution settings are applied automatically when the project is opened, but some adjustments can be made if needed.

  1. In the main toolbar, click Settings > Default fatigue solution settings.
  2. Under the General tab in the dialog, choose from the following options:
    Option Procedure
    Fatigue Method The following methods are available:
    • Uniaxial
    • Multiaxial
    SN Model Settings
    Stress Combination
    The following stress combination models are available only under uniaxial fatigue method:
    • Critical plane
    • Absolute max principal
    • Maximum principal
    • Signed von Mises
    • Signed max shear
    Tension Damage Model
    The following tension damage models are available:
    • Goodman
    • FKM - mean stress sensitivity input is required
    Shear Damage Model
    The Findley model is available for shear damage model under multiaxial fatigue method only. Findley constant and shear fatigue strength coefficient are required.
    EN Model Settings
    Stress Combination
    The following stress combinations are available only under uniaxial fatigue method:
    • Critical plane
    • Absolute max principal
    • Maximum principal
    • Signed von Mises
    • Signed max shear
    Tension Damage Model
    The following tension damage models are available:
    • Smith, Watson, and Topper
    • Morrow
    Shear Damage Model
    The following shear damage models are available only under multiaxial fatigue method:
    • Fatemi-Socie
    • Brown-Miller
    Endurance limit modifying factors
    1. Select Surface condition.

      The following options are available: polish, ground, machine, hotroll, forge.

    2. Select surface treatment.

      The following options are available: Nitrided, shotpeen, coldroll.

    3. Select fatigue strength reduction factor.
    Number of planes Enter the number of critical planes.
  3. Under the Spot weld tab in the dialog, choose from the following options:
    Option Procedure
    Model method Rupp fatigue analysis method is available.
    Mean stress correction FKM model is available.

    Mean stress sensitivity input is required.
    Thickness correction Thickness effect consideration.

    Thickness reference and thickness reference exponent inputs are required.

    TREF is used to define the reference thickness for thickness effect consideration. If the thickness of a shell (T) is greater than the specified value (TREF), the thickness effect is included by increasing the stress ( σ i j MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeq4Wdm3aaS baaSqaaiaadMgacaWGQbaabeaaaaa@39C3@ ) when thickness correction is applied: (1)
    σ ij = σ ij ( T TREF ) TREF _ N

    Default thickness reference = 25mm

    Default reference exponent = 0.2
    Endurance limit modifying factors Certainty of survival.

    Enter a value based on the scatter of the SN curve.

    Default = 0.5
    Number of angles Specify the number of angles to examine on sheet and nugget.

    Default = 20
  4. Click OK.