Maximum principal stress or strain damage

The Maxps and Maxpe damage initiation criteria are used to predict damage initiation in the XFEM enriched region.

  1. From the menu bar in the Edit Material dialog box, select MechanicalDamage for Traction Separation LawsMaxps Damage or Maxpe Damage.

    (For information on displaying the Edit Material dialog box, see Creating or editing a material.)

  2. Enter the Tolerance. The value should be equal to the tolerance within which the damage initiation criterion must be satisfied.

  3. Select the arrow to the right of the Position field, and select the method for computing the stress/strain fields ahead of the crack tip to determine if the damage initiation criterion is satisfied and to determine the crack propagation direction (if needed):

    • Select Centroid to use the stress/strain at the element centroid.

    • Select Crack tip to use the stress/strain extrapolated to the crack tip.

    • Select Combined to use the stress/strain extrapolated to the crack tip to determine if the damage initiation criterion is satisfied and to use the stress/strain at the element centroid to determine the crack propagation direction (if needed).

  4. To define material damage data that depend on temperature, toggle on Use temperature-dependent data.

    A column labeled Temp appears in the Data table.

  5. To define behavior data that depend on field variables, click the arrows to the right of the Number of field variables field to increase or decrease the number of field variables.

    Field variable columns appear in the Data table.

  6. Enter damage parameters in the Data table:

    Maximum Principal Stress or Maximum Principal Strain

    Maximum principal stress or strain at damage initiation.

    Temp

    Temperature, θ.

    Field n

    Predefined field variables.

    You may need to expand the dialog box to see all the columns in the Data table. For detailed information on how to enter data, see Entering tabular data.

  7. Select SuboptionsDamage Evolution to define the material degradation that takes place once damage begins.

    For more information, see Damage evolution.”

  8. Select SuboptionsDamage Stabilization Cohesive to enter the viscous coefficient and improve the model convergence.

    For more information, see Damage stabilization.”

  9. Click OK to exit the material editor.