[blue]Where in ACI 318 [/blue]is the subject of lateral buckling of a deep concrete beam covered??? Or is there a recent [red]Journal publication[/red] on the subject which includes design calculations???
See ACI 318 section 10.4. This is the only LTB issue in ACI that I'm aware of. It usually isn't a big issue with concrete beams due to their torsional stiffness.
The limit is a limit on the width vs. length, L/b<=50 but I'm not sure of the number. It's the only restriction I know of. Deep beams should be designed using a strut-and-tie model in which case LTB isn't a big concern.