MODCHG

Subcase Information Entry The MODCHG command can be used to remove and/or reactivate contact interfaces and/or elements for this subcase. It is used only for nonlinear analysis.

Contact activation or deactivation via TYPE=CONTACT on the MODCHG Bulk Data Entry is additionally supported for optimization runs.
Note: TYPE=ELMSET is not supported for optimization.

Format

MODCHG = option

Definitions

Argument Options Description
option <SID>

No default
SID
Set identification of a MODCHG Bulk Data Entry.

Comments

  1. MODCHG Bulk Data Entries will not be used unless selected in the Subcase Information section.
  2. For a fresh nonlinear analysis subcase (without any CNTNLSUB or with CNTNLSUB prescribed to be NO), a contact interface and a set of elements can be active or inactive depending on whether and how they are referenced by MODCHG.
    Contact and/or Elements
    Active/Inactive
    Removed with MODCHG
    Inactive
    Added with MODCHG
    Active
    Others
    Active
  3. For a subsequent nonlinear analysis subcase (with CNTNLSUB prescribed to be YES or a subcase ID), a contact interface and a set of elements can be active or inactive depending on whether and how they are referenced by MODCHG and whether they are active or not in the preceding subcase.
    Contact and/or Elements
    Active/Inactive
    Removed with MODCHG
    Inactive
    Added with MODCHG
    Active
    Others
    Active, if active in the preceding subcase
    Inactive, if inactive in the preceding subcase.