Use the user definition method to define the amplitude curve in user subroutine UAMP (Abaqus/Standard) or VUAMP (Abaqus/Explicit). For more information, see “Defining an amplitude via a user subroutine” in “Amplitude curves,” Section 34.1.2 of the Abaqus Analysis User's Guide.
To define a user-defined amplitude curve:
Display the Edit Amplitude dialog box as described in “Selecting an amplitude type to define,” Section 57.3.
In the Number of variables field, enter the number of solution-dependent state variables that must be stored with this amplitude definition.
Define the amplitude in user subroutine UAMP (for Abaqus/Standard) or VUAMP (for Abaqus/Explicit). See the following sections for more information:
Click OK to save your amplitude definition and to close the Edit Amplitude dialog box.