Creating Point Loads

Point loads represent point forces and moments applied to selected degrees of freedom. Point loads can be applied only in mechanical steps.

The magnitude of a point load can vary with time during a step according to an amplitude definition (see Amplitudes for more information on defining amplitudes). You can also apply knowledgeware techniques to control the value of a point load (for more information, see Applying Knowledgeware).

By default, the components of a concentrated force and moment applied at a point are associated with the global, rectangular Cartesian axis system. You can specify a local coordinate system for the definition of point loads, and you can define the local system as a Cartesian, cylindrical, or spherical axis system. Local coordinate systems are defined in the CATIA Part Design workbench.

Point loads can be applied to point or vertex supports, virtual parts, a point group, or a rigid coupling feature or smooth coupling feature.

This task shows you how to create a point load on geometry.

Click the Point Load icon .
The Point Load dialog box appears, and a Point Load object appears in the specification tree under the Loads objects set for the current step.
You can change the identifier of the load by editing the Name field.
Select the geometry support (a point). Any selectable geometry is highlighted when you pass the cursor over it. You can select several supports to apply the load to all supports simultaneously. You can also select a point group.
The Supports field is updated to reflect your selection. A temporary symbol will appear at each support to indicate zero values until you apply a nonzero load.
Enter values for the force components Force 1, Force 2, and Force 3.
Tip: You can drag the compass onto the model to align the directions used for specifying the force with the local model directions. For more information, see Axis System Type in the “Creating Distributed Forces” procedure in the CATIA V5 Generative Structural Analysis User's Guide.
The Force Norm field is updated to show the total resultant force that will be applied to each point.
Enter values for the moment components Moment 1, Moment 2, and Moment 3.
The Moment Norm field is updated to show the total resultant moment that will be applied to each point.
Right-click on a force or moment field to add knowledgeware controls to the selected field (for more information, see Applying Knowledgeware).
Click More to access additional point load options.
1. Toggle on Follow nodal rotation to make the direction of the force rotate with the rotation of the support point during the analysis. The force can rotate only if the underlying elements have rotational degrees of freedom and the current step accounts for nonlinear geometric effects (see Accounting for Nonlinear Geometric Effects).
2. Toggle on Selected amplitude, and select an amplitude from the specification tree to define a nondefault time variation for the point load.
  If you do not specify an amplitude in a Nonlinear Structural case, Abaqus applies the reference magnitude based on the Default load variation with time option that you selected when you created the step. Abaqus either applies the reference magnitude linearly over the step (Ramp) or applies it immediately at the beginning of the step and subsequently holds it constant (Instantaneous).
  If you do not specify an amplitude in an Explicit Dynamics case, Abaqus applies the reference magnitude immediately at the beginning of the step and subsequently holds it constant (Instantaneous).
  See About Prescribed Conditions in the Abaqus Prescribed Conditions Guide for more information.
3. Toggle on Selected local system, and select a coordinate system to define local directions.
4. If desired, change the local orientation from Cartesian to Cylindrical or Spherical. See Using Local Coordinate Systems for more information.
Click OK in the Point Load dialog box.
Symbols representing the applied force and moment are displayed on the geometry.