Adding constraints

All but Custom Constraints use Heads Up Display (HUD) and grips to define the inputs easily. More complex settings are available in the dialog boxes. When you select Use HUD in Application option in the Frame Analysis Settings dialog box, Heads Up Display is used as default input method.

Constraints are defined in the global coordinate system.

The available constraint types are:

Access	Constraint Type	Used to...
	Fixed	Apply fixed constraint when no movement (rotation and displacement) is allowed on beam or node.
	Pinned	Apply pinned constraint when no displacement and free rotation is allowed on beam or node.
	Floating Pinned	Apply floating pinned constraint when free rotation and free displacement in one plane is allowed on beam or node.
	Custom	Apply custom constraint to specify your own degrees of freedom of displacement and rotation on beam or node.

To add a structural ( fixed, pinned, floating, or custom) constraint:

1. On the ribbon, click the constraint command for the type of constraint you are adding.
   Note: You can also right-click the Constraints node in the browser and select the appropriate constraint type from the context menu.
2. Select beam or node to position the constraint. Drag the glyph to specify the offset. You can define offset using absolute or relative values. The HUD always corresponds to the currently selected grip. Enter an exact value of the given parameter directly.
3. To display a corresponding dialog box, right-click in the graphics window, and select More Options.
4. In the dialog box, the select command is active so you can immediately select the constraint location. Select node or beam as the origin of the constraint.
5. For complex cases, you can define the constraint with all the detailed information. Select a beam or node, and click the Custom command. In the dialog box, define degrees of freedom of displacement and rotation, and so on.
6. Select OK to add the constraint and close the dialog box.

To apply a custom constraint

Custom constraint enables you to customize all parameters of the constraint (position, orientation, degrees of freedom for rotation and displacement on beam or node).

To set the custom constraint values, use the Custom Constraint dialog box, or drag the grips in the graphics window. Heads Up Display input is not available.

On the ribbon, click Frame Analysis tab Constraints panel Custom . Select beam or node to position the constraint. Using the Absolute or Relative check boxes, select how you want to set the offset value. Set the Offset value. Set angles of constraint rotation about X, Y, and Z axes. Values are defined in the global coordinate system. Specify the displacement. Use the drop-down menus to specify the degrees of freedom for X, Y, and Z axes. When you select Fixed option, there is no displacement allowed in this direction. Uplift none, Uplift+ and Uplift- specify displacements in X-axis, Y-axis, and Z-axis in the compatible ("+") or opposite ("-") direction with respect to the axis of the beam local coordinate system. Click here to read more about types of displacement. Specify the rotation. Use the drop-down menus to specify the degrees of freedom for X, Y, and Z axes. When you select Fixed option, there is no rotation allowed in this direction. Uplift none, Uplift+ and Uplift- specify rotations in X-axis, Y-axis, and Z-axis in the compatible ("+") or opposite ("-") direction with respect to the axis of the beam local coordinate system. Click here to read more about types of rotation.