To define new or to edit existing rules for generating automatic load combinations, use the following procedure.

1. On the Loading ribbon tab, select the Automatic Combinations > Edit Auto Combination Rules tool in the Load Generation group .
   
   The Edit Loading Rules for Auto Load Combination Generation dialog opens.
2. (Optional) To create a new Code and Category of load combinations:
   1. Click New Code. The Add New Code dialog opens.
      
   2. Type a Code Name and then click OK. A new, empty table is loaded.
   3. Click New Category. The Add New Category dialog opens.
      
   4. Type the Category Name and the No. of Rules to initially create in the table. You can add or remove table rows after you create the table.
   5. Click OK. The specified rows are added for the new table.
3. For each load type (i.e., column):
   1. Set the Include Notional Loads? check box to include notional loads in this type for direct analysis. Notional loads are included by default only in dead, live, roof life, snow, and ice load types.
   2. Select the appropriate Combination Rule option for this load type:
      • Aggregate - Combine all cases together: For each rule, a single combination will be created which will include all the load cases of that load category multiplied by the factor in the table.
      • Separate - Separate combination for each case: For each rule, multiple combinations will be created, each will include one of the load cases of that load category multiplied by the factor in the table.
      • Matrix - All possible combinations: For each rule, multiple combinations will be created which will include each of the load cases of that load category on their own and with each and every other load case of that category multiplied by the factor in the table.
4. For each combination (i.e., row) in the table, specify the load multiplier for the load types present in that load combination.
   Tip: To add a new row, click Add Row. To remove a row, click the row number to highlight the entire row and then press <Delete>.
5. To save the changes to a table, click Update Table.
6. Repeat steps 3, 4, and 5 individually as needed to specify the load combinations for the code category.
7. Click Close.