In the model of a building that am designing, the composite beams, which are lateral, are being checked in RAM steel post processor. I have not assigned an unbraced length, yet the composite beams are indicating an unbraced length of 7.86 for lateral torsional restraint. Could anyone please explain how the beam is picking this up? Thanks in advance.
A gravity beam (not shown) is probably bracing it. See also: https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/25946/ram-steel-beam-unbraced-length
Thanks for the response. The beam in question does not have any gravity member framing into it. It runs a span of 40f. Is there something else that might be causing the composite beam to show 7.86' as unbraced length?
Inflection point is an optional brace point (criteria - flange bracing) assuming the beam has moment reversal.
Answer Verified By: Nik
Thank You! I assumed the inflection point was turned off in the beam module. Was not aware of the option being present in the frame module. Turned it off and I see the correct unbraced length, which is the entire length of the beam. I appreciate your help!