Defining Surface-Based Contact in Explicit Dynamic Steps

You can apply surface-based contact to define the interaction behavior between two discrete surface regions in the model.

See Also
About Surface-Based Contact
In Other Guides
About Step-dependent Actions
  1. From the Interactions section of the action bar, click Surface-based Contact .
  2. Optional: Enter a descriptive Name.
  3. Select Let system determine main/secondary assignment to allow the app to specify the main surface and secondary surface assignments automatically.
    The dialog box indicates the two faces as Surface 1 and Surface 2 and disables the swap option.
  4. Select the geometry supports in the model.

    You must apply surface-based contact must be applied between one or more faces or analytical rigid surfaces as the Main support and one or more faces as the Secondary support.

    Tip: When the contacting surfaces are difficult to discern, you can render all surfaces translucent except for those surfaces that contact each other.
    • Click green to render all surfaces translucent except for the main surfaces.
    • Click magenta to render all parts translucent except for the secondary surfaces.

  5. Optional: If the geometry supports include surface (shell) geometry, click to change the side of the surface to be considered in the contact interaction.
  6. Optional: If necessary, click to swap the Main and Secondary supports.
  7. From the Contact property options, select the name of a predefined contact property to be associated with this surface contact feature.

    If you do not choose a specific property, the app applies a default penalty contact. The default penalty contact provides a basic type of contact in which the penalty stiffness is constant, so the pressure-overclosure relationship is linear. The penalty stiffness is set to 10 times a representative underlying element stiffness.

    Note: The default penalty contact is different from having no contact property selected at all.

  8. From the Tie surfaces options, select one of the following:
    OptionDescription
    Within specified tolerance Ties together surfaces that are within the tolerance that you specify for the duration of the simulation; that is, no relative motion between the surfaces occurs at contacting interfaces. The app does not tie together surfaces outside of the tolerance.
    Default Ties together surfaces that are within the default tolerance of each other. The default tolerance value is 5% of the characteristic element length. The app does not tie together surfaces that are farther away from each other than the deafult tolerance.
    Compute tolerance from geometry Ties together surfaces regardless of the separation distance.

    A sufficiently large tolerance is computed automatically and used in the Abaqus solvers.
  9. Enter a value for the Specify main/secondary weighting, which is the weighting factor for the contact surfaces. The following values are valid:
    OptionDescription
    1.0 Designates the first surface in the contact pair as the main surface and the second surface as the secondary surface.
    0.5 Uses the balanced main-secondary contact algorithm.
    0.0 Designates the first surface in the contact pair as the secondary surface and the second surface as the main surface.
  10. Click OK.