Load Combination Data Form

Use the Load Combination Data form to specify the load combination name, type, and the load(s) with scale factor to be included in the combination.

Note: This form also displays in an non-editable format when a design load combination ID is highlighted on the Design Load Combinations Selection - {Type} form and the Show button is clicked.

Load Combination Name edit box. Use the default or specify another name for the load combination in this edit box. Note that each load combination and load case must have a unique name. Also, the word Mode is reserved and cannot be used for either a load case name or a load combination name.
Load Combination Type drop-down list. Specify the type of load combination The most common type of load combination is ADD (Additive).
- Linear Add option. The Combo maximum is an algebraic linear combination of the maximum values for each of the included analysis cases. Similarly, Combo minimum is an algebraic linear combination of the minimum values for each of the included analysis cases.
- Envelope option. The Combo maximum is the maximum of all of the maximum values for each of the included analysis cases. Similarly, the Combo minimum is the minimum of all of the minimum values for each of the included analysis cases.
- Absolute Add option. The Combo maximum is the sum of the larger absolute values for each of the included analysis cases. The Combo minimum is the negative of the Combo maximum.
- SRSS option. The Combo maximum is the square root of the sum of the squares of the larger absolute values for each of the included analysis cases. The Combo minimum is the negative of the Combo maximum.
- Range Add option. The combined maximum is the sum of the positive maximum values from each of the contributing cases (a case with a negative maximum does not contribute), and the combined minimum is the sum of the negative minimum values from each of the contributing cases (a case with a positive minimum does not contribute). This Combo Type is useful for pattern or skip-type loading where all permutations of the contributing load case must be considered.
Modify/Show Notes button. Click this button to display the Load Combination Notes form, where notes about load combinations can be entered and viewed.
Auto Combination display box. This display box will indicate if the combination has been created automatically (Yes) or not (No).
Define Combination of Load Case/Combo Results area, Load Name drop-down list and Scale Factor edit box. The actual load combination is created by specifying one or more load cases, each with an associated scale factor.
- Add button. Add a load case to the load combination definition as follows:
- 1. Select the load case name from the Load Name drop-down list.
  2. Use the default or enter another value for the scale factor in the Scale Factor edit box.
  3. Click the Add button.

Note: A modal load case along with a mode number can be specified as one of the loads to be included in the load combination. The Mode column, which can be used to specify a mode number, is present in the form only when at lest one modal load case is included in the load combination definition.

Note: More than one instance of the same load case (or combination) can be used in a load combination.

- Delete button. Delete a load case from the load combination definition as follows:
- 1. Highlight the name of the load case to be deleted in the Case Names display box (not the drop-down list ).
  2. Click the Delete button.