Predeformation
Use the Predeformation subnode to specify that the elastic forces in the Spring Foundation or Spring Material are nonzero at zero displacement. Thus, you can model cases where the unstressed state of the spring is in another configuration than the one described by the geometry.
The value of the predeformation can vary during the simulation, so it should not be interpreted as an initial value.
Shell Properties

 
This section is only present in the Layered Shell interface, where it is described in the documentation for the Predeformation node.
Spring Predeformation
Based on space dimension, enter the values for the Spring Predeformation u0.
You can assign the load caused by the predeformation to a load group. See Load Cases in the Structural Mechanics Modeling chapter.
Location in User Interface
Context Menus
Solid Mechanics>Spring Foundation>Predeformation
Solid Mechanics>Thin Layer>Spring Material>Predeformation
Shell>Spring Foundation>Predeformation
Layered Shell>Spring Foundation>Predeformation
Layered Shell>Spring Foundation, Interface>Predeformation
Layered Shell>Thin Elastic Layer>Predeformation
Plate>Spring Foundation>Predeformation
Membrane>Spring Foundation>Predeformation
Beam>Spring Foundation>Predeformation
Truss>Spring Foundation>Predeformation
Wire>Spring Foundation>Predeformation
Multibody Dynamics>Spring Foundation>Predeformation
Ribbon
Physics tab with Spring Foundation, Spring Foundation, Interface, or Spring Material node selected in the model tree:
Attributes>Predeformation