How to Sum Reaction Forces

Figure 1: Note the locations of the pressure loads and constraints in this display of the vertical reaction forces in the cutting frame. Figure 2: The "Inquire: Results" dialog displays information about the selected nodes and the calculated "Summary" value.

The summation of reaction forces in a model is often used to verify input loadings, validate model behavior or determine floor load distributions. In the Superview IV Results environment, the "Inquire: Results" dialog can be used to sum the reaction forces of selected nodes.

Another typical application of summing reaction forces is to determine the total force of a pressure load when the area of pressure is unknown and cannot be readily calculated. As shown in Figure 1, the cutting frame has a pressure load applied to two surfaces of unknown area and is fully constrained at the bottom of each of the four legs. The total force of the pressure can be calculated by summing the vertical reactions of all of the constrained nodes.

To sum the reaction forces in the Superview IV Results environment:

• display the desired reactions using the "Results: Reaction Vector" menu;
• select the nodes that will be used in the summation;
• right click anywhere in the working area;
• in the pop-up menu that appears, select "Inquire Results"; and
• in the "Inquire: Results" dialog (Figure 2), click on the "Summary" pull-down menu and select "Sum".

The summary of the reaction forces of all selected nodes will now be displayed in the "Inquire: Results" dialog. If desired, the area could be calculated since the pressure and force values are now known.

For more information about reaction forces and inquiring on results, see the ALGOR User’s Guide and the "How to Inquire on Results at a Specific Location" Tech Tip.