AD.2007-1001.1.12 Reference Load Cases
Large models can include multiple load cases which do not require analysis in their own right and are simply the building blocks for inclusion in primary load cases. This is similar to a REPEAT LOAD command, but has the added benefit of not being solved in its own right.
A reference load case is listed in the Load dialog box of the General Load Page of the modeling mode. A Reference load case is listed in the Definitions section of the data file and displayed thus:
To add a new Reference load case, highlight the Reference Load Definitions in the Load dialog and click on the Add button. Provide the title for the load case and number (however, similar to that of creating Primary load cases, the next available reference load case number. Note that these reference load case numbers can be the same as a primary or combination load case number (however a combination load case number cannot be the same as a primary load case number).
The Reference load case names are shown in the Load dialog box. Load items should then be added to this load case in exactly the same way as adding load items into a primary load case.
Select the Reference load case and click on the Add button to display all the load items that can be added to this load case, thus:
To be analyzed, the loads defined in a Reference load case must be added to one or more Primary load cases. This is done by selecting the required primary load case and clicking on the Add button.
Select the load item:
Select the required defined Reference load cases and click on the [>] button to select them for inclusion in the current load case. The >> button will select all defined Reference Load cases.
These are added with a factor of 1.0, however, each can be modified with its own specific multiplication factor:
The format of the definition of a Reference Load (i) in the data file is thus:
DEFINE REFERENCE LOADS LOAD R(i) LOADTYPE (type) TITLE REF LOAD CASE 1 (Load items) … END DEFINE REFERENCE LOADS
The format of a reference to a Reference Load in a primary load (j) case is thus:
LOAD (j) LOADTYPE (type) TITLE LOAD CASE 1 REFERENCE LOAD R(i) 1.0 …