As noted in the subject title, I'm having issues with getting the hat channel members (purlins) to pass in my 3D model. The members pass if I do a bending check by hand using the same gravity load and section modulus shown in the model (Sy=Iy/c). As you can see I assigned one of the purlins to be a 1"x1-14ga tube steel member to check and see if it would pass. I picked this section due to it having similar section properties as the hat channel except it is a closed shape. Any advice on how to analyze the hat channels in STAAD so that they are only seeing axial bending from the gravity/uplift loading would be greatly appreciated. Also, please address any other errors you may notice in my model.
P.S. I did reference Section F.1 of the Steel Manual to check and see the failure mode that the hat channel was under, but I didn't get much context from the section. Also, the actual building will be 100' long and have 26 frames, I attached only a 3 frame section for simplicity. Thank you!
100x (1.5' & 3' Chord Spacing) Frame.STD
Please attach user tables DOUBLE 2.25-12GA.UPT and 1.25IN-18GA.UPT.
Sorry about that, it will not allow me to attach the UPT files. I have attached the dxf files to import into the section builder so you can make your own UPT files.
1.25in-18ga.dxf2.25in-12ga Double Tube.dxf
Try to add those UPT files into a zip archive and attach it again.
Let me know if this works.
For STAAD Ref.7z
UPT sections which have a General type are designed as an approximated I section in STAAD.Pro. STAAD does not design it as a Hat section or some other section (with the only exception for EN 1993-1-1:2005 code). Some more information can be found here: communities.bentley.com/.../612745
How do you suggest I model it in order to get the most accurate answer as possible if I cannot actually analyze the correct shape of the section itself? Is there a certain section shape I can designate the hat channel as and manually input the section properties to reflect that of the hat channel? Thank you for your help so far.