Thanks Mjkkb2 - I have had the same thoughts.
However, I question how dated the Flexible diaphragm approach is. The reason being is that the deck has stiffness, it has load-carrying capacity, it has capability of transferring load right?
What are other engineer's takes on diaphragm modeling of a typical untopped metal roof deck?
Consider 1 1/2" Vulcraft Type B, 20 GA (design thickness = 0.0358in). I use RAM Structural System's Frame module for my lateral analysis of steel framed buildings with the following parameters for this...
