This defines imposed displacements on structure support nodes. Open the Imposed Displacement dialog by clicking 
in the Load Definition dialog.
You can define the following imposed displacements for structure support nodes in this dialog:
- Displacements U along the X, Y or Z axis of the coordinate system
- Rotations R acting about the X, Y or Z axis of the coordinate system.
Imposed displacements act in the local coordinate system of a rotated support.
Note: Imposed displacements can be defined only in directions that are blocked or elastic for a given support.
At the bottom of the dialog, Load treated as field has the following options:
- Displacement
- Velocity
- Acceleration.
Note: The imposed displacement of a supported node can be used in static calculations for a structure and in the time history analysis for a structure.
The imposed velocity or acceleration on a supported node is applied only in the time history analysis; this type of load in the static analysis has no effect.
In the time history analysis, imposed loads change according to the time function used.