Joint Loads - Forces

Form: Joint Forces

The force load is used to apply concentrated forces and moments at the joints. Values may be specified in a fixed coordinate system (global or user-defined system) or the joint local coordinate system. All forces and moments at a joint are transformed to the joint local coordinate system and added together. Forces and moments applied along restrained degrees of freedom add to the corresponding reaction, but do not otherwise affect the structure.

Select one or more joints to be assigned a force load.
Click the Assign menu > Joint Loads > Forces command to access the Joint Forces form.

- Load Pattern Name drop-down list. Select the load pattern to which the force load is being added. Alternatively, click the + (plus symbol) beside the drop-down list to access the Define Load Patterns form; use the form to define a load pattern that will then be available in the drop-down list.
- Units drop-down list. If necessary, use the Units drop-down list to change the units for this form.
- Loads edit boxes. Enter values for the Forces and Moments in the appropriate edit boxes.
- Coordinate System drop-down list. Select the coordinate system for the load from the drop-down list.
- Options. Specify how the load will be applied.
- Add to Existing Loads: Adds the specified force to the Joint. If one or more force assignments have already been made, this option increases the existing force, assuming that a positive force is being specified.
- Replace Existing Loads: Replaces the currently specified force, if any, with the new assignment. If no assignment exists, the new assignment is still made. This is the default option.
- Delete Existing Loads: Deletes any and all force assignments made to the selected joint(s). When this option is selected, the items in the Loads area of the form are ignored when the OK button is clicked.

The window will refresh with a graphical representation of the load assigned on the selected joints.

Example: Assignment of joint load forces is demonstrated in Problem A, Problem B, Problem D, Problem E, Problem J, Problem K, Problem L, Problem M, Problem N, Problem P, Problem Q, and Problem S.