STAAD.Pro Help

D. To design steel members in groups

To design members as a group, use the following procedure.

In many situations, it is preferable to have only a few different member sizes for many members rather than each member size be different, even if this would result in some members being underutilized. You can group members in the batch design to instruct the program to replace the member sizes in the group with the highest capacity member of the existing sizes in that group. You can also instruct the program to use a specified section property for the grouping or even group based on a specific member number, regardless of property specifications.

For example, in a floor bay with 5 beam members the edge members were selected as W12x14 shapes and the interior members were selected as W14x22 shapes. Grouping these members will immediately instruct the program to use W14x22 for all members for any subsequent instructions (i.e., analysis, design, take-off, etc.).

Note: All members within a group must be of the same cross section type. If one or more of the members has a different cross-setion type, the grouping is ignored by the program.
  1. On the Steel Design - Whole Structure dialog, click Commands. The Design Commands dialog opens. The tabs (if any) available in this dialog are dependent on the current design code selection. Not all commands are available for every design code.
  2. If you want to retain the member groups for all subsequent commands, select the FIXED GROUP tab and then click Add. If you do not use the FIXED GROUP option, then the members are grouped once and then this grouping is ignored for subsequent commands. If you do add the FIXED GROUP command, then all subsequent member selection commands will apply to the group again.
  3. Select the GROUP tab.
  4. (Optional) Select the Property Specification to use for grouping shapes.
  5. (Optional) Check the Same as Beam # option and then select a member number from the drop-down list.
  6. Click Add.
  7. Click Close.
  8. Assign the group command to all the members you want to group together.
You can repeat this procedure to create as many design groups as necessary.

Once you have created a group, you will typically want to perform a code check or member selection on the members.