Member Bracing Types - Lateral Torsional Buckling

The Member Bracing Types Braced at Member Ends and Braced at All Supports are the same thing for a single span beam. 
It means that there's some framing at the bearing points to keep the beam from falling over or trying to rotate, but that's all. 
If more than 1 span, then those two (above) are different depending on whether there is framing at the interior support(s) to provide that same kind of resistance to rotation. 
We typically refer to the Braced at ends condition as "fully unbraced" meaning that there's nothing within the span providing bracing.  This is often the right case for a garage door header.  If there's any framing that can provide the resistance to rotation or lateral displacement within the span, then it becomes a case of determining if it is enough to consider it fully braced or if the user needs to determine the distance between discrete bracing points and do the user defined (Specify Unbraced Length) input approach.
Have more questions? Submit a request