Steel Beam Size Restrictions

You can assign specific sizes to steel beams using Layout - Beam - Assign Size which is nice for evaluating existing structures. In this case, we want the program to pick the beam sizes for us, but we want to make sure all the cantilever beams are the same

Note: When a gravity beam cantilevers over another beam or column, the behavior is assumed to be that of a fulcrum. No moment is transferred into the supporting member. If you want moment to be transferred as in the case of a fully restrained moment connection, then the beam and the support should be modeled as Lateral members. With lateral members, you can control the end fixity of all the members.

Select the 2nd level type.
Set the Current Material to Steel.
Select Layout > Beams > Size Restrictions.
Check the Maximum depth limit and set it to 11 (275)
Check the Minimum depth option and set it to 9 (225).
Note: These limits are literal limits on the beam depth. We are using a depth range here to insure that we get nominal 10" beam.
Click [Fence] and fence the entire Atrium canopy.
Note: While you are in the Steel material mode you cannot alter concrete beams.
Repeat this for the 3^rd story level Atrium beams.

With the Options > Set Show Options command, you can confirm the attributes assigned to the model graphically. For example, you can use that feature to highlight all beams with an assigned size restriction.

Select the Roof level type.
Set the Current Material to Steel Joist.
Right click and to return to the Size Restriction dialog.
Check to use only a Maximum Depth of 24 (600).
Click [Fence] and select all of the joist girders on Line 3.

Note: For joist girders, the maximum depth field is used explicitly in labeling the member. These joists will not be deeper than 24", they will be exactly 24" deep. For more on the design labeling of joists and joist girders, refer to the online documentation for the Steel beam module.