We have an existing flat roof 35' x 35' that was under designed and needs additional support. The flat roof is currently supported by 22k7 open web steel joists 5'-7" O.C (35' span). Based on structural calcs, the existing joist spacing is insufficient. We are proposing to add additional 22k7's between the existing joists (proposed spacing of 2'-9.5") and a W-shape at mid span for additional support. Can the W-shape support the 22k7 from its bottom chord or should the existing 22k7's be replaced to so that they are supported from their top chords? Also can it be assumed that the w-shaped has continuous support if the bottom chord of the 22k7 is welded to the w-shape?
Any recommendation or different ideas would be appreciated.
Red Flag Submitted
Thank you for helping keep Eng-Tips Forums free from inappropriate posts. The Eng-Tips staff will check this out and take appropriate action.
Reply To This Thread
Posting in the Eng-Tips forums is a member-only feature.