Initial Stress and Strain
You can add the Initial Stress and Strain subnode to the Linear Elastic Material, in order to specify the stress or strain state in the structure before applying any constraint or load. The values given are not initial values in the mathematical sense, but rather a contribution to the constitutive relation
In many cases Initial Stress and Strain and External Stress are interchangeable when prescribing stresses, but you can find some more options in the latter.
Initial Stress and Strain
Enter an Initial axial strain eni and Initial axial stress σni.
For details about initial stresses and strains, see Inelastic Strain Contributions and Initial Stresses and Strains.
Location in User Interface
Context Menus
 Truss>Linear Elastic Material>Initial Stress and Strain
Ribbon
Physics tab with Linear Elastic Material node selected in the model tree:
Attributes>Initial Stress and Strain