I am modelling a multi storey building with 4 composite floors and I have encountered the following problems:
- using a composite deck I get VERY large deflections, of approximately 700mm, this makes me think it is not working as a Diaphragm. How can I resolve this?
- using diaphragm mode in STAAD, I get no axial forces in my steel beams, especially in those in the brace bays, this makes me think all the forces are absorbed by the more stiff concrete and none are transferred into the steel. This would be ok if I could export the forces in the diaphragm and use it to determine the forces in the steel. However, so far I haven't been able to find a way to get any output from the diaphragm.
What am I doing wrong? Any help would be greatly appreciated.
Agata