Specifying contact formulation assignments for general contact

Attributes for a general contact interaction, such as contact formulation, are specified independently of the contact domain in the Attribute Assignments portion of the interaction editor.

For a brief overview of general contact, see Understanding interactions. For a more detailed discussion of main-secondary formulations, see Contact Controls Specific to General Contact in Abaqus/Standard and Contact Formulation for General Contact in Abaqus/Explicit.

This task shows you how to:

See Also
Interaction editors
Defining general contact
In Other Guides
Contact Controls Specific to General Contact in Abaqus/Standard
Contact Formulation for General Contact in Abaqus/Explicit

Specify main-secondary assignments for general contact

Context:

By default, Abaqus/Standard automatically assigns a main and a secondary role to each surface in an interacting pair; Abaqus/Explicit uses a balanced main-secondary formulation for all surfaces (except node-based surfaces and analytical rigid surfaces). You can override the default assignments and directly specify the main-secondary assignments for surface pairings in a general contact interaction.

  1. Display the general contact interaction editor using one of the following methods:

    • To create a new general contact interaction, follow the instructions in Defining general contact.

    • To edit an existing general contact interaction, select Interaction Edit interaction name from the main menu bar.

  2. Click the Contact Formulation tab in the Attribute Assignments portion of the interaction editor.
  3. Click next to the following field:

    • Main-secondary assignments for Abaqus/Standard general contact definitions.

    • Pure main-secondary assignments for Abaqus/Explicit general contact definitions.

    The Edit Main-Secondary Assignments dialog box appears. By default, when you select a surface from the list or the table, Abaqus/CAE highlights the surface in the viewport; however, highlighting does not apply for (Global) and (Self). You can turn off Highlight selected regions at the bottom of the dialog box to turn off selection highlighting.

  4. Select one or more surfaces from the list of existing surfaces in the first column on the left side. Select (Global) to assign a pure main-secondary weighting for contact between the entire contact domain and an individual surface.

    Tip: You can click to define a new surface and add it to the list. See Creating surfaces for instructions on defining surfaces.

  5. Select the second surface or surfaces from the list of existing surfaces in the second column to define the surface pairings.

    • When multiple surfaces are selected in either column, all possible combinations will be generated.

    • For Abaqus/Standard general contact definitions, select either the same surface name or (Self) in the second column to specify a balanced main-secondary formulation for self-contact interactions on a particular surface.

    • If the main and secondary surfaces overlap, self-contact is excluded for the overlapping regions.

  6. Click the arrows in the middle of the dialog box to transfer your selections to the list of main-secondary assignments.

    The table on the right side of the dialog box is updated to reflect your selections.

  7. Specify the type for the first surface in the last column of the Main-Secondary Assignments table.

    • Select SECONDARY to indicate the first surface is the secondary surface.

    • Select MAIN to indicate that the first surface is the main surface.

    • Select BALANCED to specify balanced main-secondary contact between the two surfaces (available only in Abaqus/Standard).

    For self-contact surface pairings, you must select BALANCED.

  8. Repeat the above steps as needed to complete the main-secondary assignments. If you want to delete main-secondary assignments, select the rows and click .
  9. Click OK to save your selections.

    The interaction editor reappears with updated information on the number of directly specified main-secondary assignments.

  10. Click OK to create the interaction and to close the editor.

Specify polarity assignments for general contact

  1. Display the general contact interaction editor using one of the following methods:

    • To create a new general contact interaction, follow the instructions in Defining general contact.

    • To edit an existing general contact interaction, select Interaction Edit interaction name from the main menu bar.

  2. Click the Contact Formulation tab in the Attribute Assignments portion of the interaction editor.
  3. Click next to the Polarity assignments for Abaqus/Explicit general contact definitions.

    The Edit Polarity Assignments dialog box appears. By default, when you select a surface from the list or the table, Abaqus/CAE highlights the surface in the viewport; however, highlighting does not apply for (Global). You can toggle off Highlight selected regions at the bottom of the dialog box to turn off selection highlighting.

  4. Select one or more surfaces from the list of existing surfaces in the first column on the left side. Select (Global) to assign a polarity weighting for contact between the entire contact domain and an individual surface.

    Tip: You can click to define a new surface and add it to the list. See Creating surfaces for instructions on defining surfaces.

  5. Select the second surface or surfaces from the list of existing surfaces in the second column to define the surface pairings.

    • When multiple surfaces are selected in either column, all possible combinations will be generated.

    • If the surfaces overlap, self-contact is excluded for the overlapping regions.

  6. Click the arrows in the middle of the dialog box to transfer your selections to the list of polarity assignments.

    The table on the right side of the dialog box is updated to reflect your selections.

  7. Specify the option in the third column of the Polarity Assignments table, to indicate the side of the (double-sided) elements in the second surface.

    • Select SPOS to indicate that the SPOS side of the (double-sided) elements in the second surface should be considered for contact with the first surface.

    • Select SNEG to indicate that the SNEG side of the (double-sided) elements in the second surface should be considered for contact with the first surface.

    • Select TWO_SIDED to indicate that both sides of the (double-sided) elements in the second surface should be considered for contact with the first surface.

  8. Repeat the above steps as needed to complete the polarity assignments. If you want to delete polarity assignments, select the rows and click .
  9. Click OK to save your selections.

    The interaction editor reappears with updated information on the number of directly specified polarity assignments.

  10. Click OK to create the interaction and to close the editor.

Specify sliding transition assignments for general contact

  1. Display the general contact interaction editor using one of the following methods:

    • To create a new general contact interaction, follow the instructions in Defining general contact.

    • To edit an existing general contact interaction, select Interaction Edit interaction name from the main menu bar.

  2. Click the Contact Formulation tab in the Attribute Assignments portion of the interaction editor.
  3. Click next to the Sliding Transition assignments for Abaqus/Standard general contact definitions.

    The Edit Sliding Transition Assignments dialog box appears. By default, when you select a surface from the list or the table, Abaqus/CAE highlights the surface in the viewport; however, highlighting does not apply for (Global) and (Self). You can turn off Highlight selected regions at the bottom of the dialog box to turn off selection highlighting.

  4. Select one or more surfaces from the list of existing surfaces in the first column on the left side. Select (Global) to assign a sliding transition weighting for contact between the entire contact domain and an individual surface.

    Tip: You can click to define a new surface and add it to the list. See Creating surfaces for instructions on defining surfaces.

  5. Select the second surface or surfaces from the list of existing surfaces in the second column to define the surface pairings.

    • When multiple surfaces are selected in either column, all possible combinations will be generated.

    • For Abaqus/Standard general contact definitions, select either the same surface name or (Self) in the second column to specify a formulation for self-contact interactions on a particular surface.

    • If the surfaces overlap, self-contact is excluded for the overlapping regions.

  6. Click the arrows in the middle of the dialog box to transfer your selections to the list of sliding transition assignments.

    The table on the right side of the dialog box is updated to reflect your selections.

  7. Specify the smoothness of the contact force redistribution on sliding in the third column of the Sliding Transition Assignments table.

    • Select ELEMENT_ORDER_SMOOTHING to indicate the smoothness of the contact force redistribution on sliding should be of the same order as the elements underlying the secondary surface.

    • Select LINEAR_SMOOTHING to indicate linear smoothness of the contact force redistribution on sliding.

    • Select QUADRATIC_SMOOTHING to indicate quadratic smoothness of the contact force redistribution on sliding.

  8. Repeat the above steps as needed to complete the sliding transition assignments. If you want to delete sliding transition assignments, select the rows and click .
  9. Click OK to save your selections.

    The interaction editor reappears with updated information on the number of directly specified sliding transition assignments.

  10. Click OK to create the interaction and to close the editor.

Specify edge-to-edge formulation assignments for general contact

  1. Display the general contact interaction editor using one of the following methods:

    • To create a new general contact interaction, follow the instructions in Defining general contact.

    • To edit an existing general contact interaction, select Interaction Edit interaction name from the main menu bar.

  2. Click the Contact Formulation tab in the Attribute Assignments portion of the interaction editor.
  3. Toggle on Edge-to-Edge formulation assignment for Abaqus/Standard general contact definitions.
  4. Specify the Formulation.

    • Select BOTH to activate both formulations for edge-to-edge contact.

    • Select NO to deactivate edge-to-edge contact.

    • Select RADIAL to activate the radial edge-to-edge contact formulation.

    • Select CROSS to activate the formulation based on the cross product of the edge directions for edge-to-edge contact.

  5. Click OK to create the interaction and to close the editor.

Specify sliding formulation assignments for general contact

  1. Display the general contact interaction editor using one of the following methods:

    • To create a new general contact interaction, follow the instructions in Defining general contact.

    • To edit an existing general contact interaction, select Interaction Edit interaction name from the main menu bar.

  2. Click the Contact Formulation tab in the Attribute Assignments portion of the interaction editor.
  3. Click next to the Sliding formulation assignments for Abaqus/Standard general contact definitions.

    The Edit Sliding Formulation Assignments dialog box appears. By default, when you select a surface from the list or the table, Abaqus/CAE highlights the surface in the viewport; however, highlighting does not apply for (Global) and (Self). You can turn off Highlight selected regions at the bottom of the dialog box to turn off selection highlighting.

  4. Select one or more surfaces from the list of existing surfaces in the first column on the left side. Select (Global) to assign a sliding formulation for contact between the entire contact domain and an individual surface.

    Tip: You can click to define a new surface and add it to the list. See Creating surfaces for instructions on defining surfaces.

  5. Select the second surface or surfaces from the list of existing surfaces in the second column to define the surface pairings.

    • When multiple surfaces are selected in either column, all possible combinations will be generated.

    • For Abaqus/Standard general contact definitions, select either the same surface name or (Self) in the second column to specify a formulation for self-contact interactions on a particular surface.

    • If the surfaces overlap, self-contact is excluded for the overlapping regions.

  6. Click the arrows in the middle of the dialog box to transfer your selections to the list of sliding formulation assignments.

    The table on the right side of the dialog box is updated to reflect your selections.

  7. Select the sliding value in the third column of the Sliding Formulation Assignments table.

    • Select Small Sliding to specify the surface pairings to consider for the small-sliding approach.

    • Select None to exclude the surface pairings in the small-sliding approach.

  8. Repeat the above steps as needed to complete the sliding formulation assignments. If you want to delete sliding formulation assignments, select the rows and click .
  9. Click OK to save your selections.

    The interaction editor reappears with updated information on the number of directly specified sliding formulation assignments.

  10. Click OK to create the interaction and to close the editor.

Specify beam cross-section for general contact

  1. Display the general contact interaction editor using one of the following methods:

    • To create a new general contact interaction, follow the instructions in Defining general contact.

    • To edit an existing general contact interaction, select Interaction Edit interaction name from the main menu bar.

  2. Click the Contact Controls Assignment tab in the Attribute Assignments portion of the interaction editor.
  3. Toggle Beam Cross Section assignment for Abaqus/Explicit general contact definitions.
  4. Specify the Beam Cross Section assignment:

    • Select CIRCUMSCRIBED CIRCLE to activate contact calculations based on a circumferential approximation of the beam element.

    • Select EXACT to activate contact calculations based on the actual cross section of the beam element.

  5. Click OK to create the interaction and to close the editor.