Beam theory usid in Simulate

hi all,

I'm trying to figure out what beam theory is used in Simulate with beam elements.

Is it Timoshenko's theory is which a section can rotate or is it Eulers-Bernouillis theory in which a cross section is always considered to be perpendicular to the neutral viber?

Unfortunately i cannot trace it in the help-files (is the anwer very well hidden in there?) .

Thanks,

Peter