Large UZ force in one of the slabs

[structengineerintraining]

Hey everyone,

I'm a student and currently working on a client's project.

I have an issue where my etabs model is not showing errors when checking the model. However, when running the analysis, I get a large UZ displacement on one side of the building. I am guessing this issue is on the roof of the building due to the snow load, hence passing it onto the floors underneath. I have attached the file for anyone to look at and suggest what to do.

I have looked for hours on tutorials online but to no use. I have shared EDB and E2K file types for the model. Let me know if you encounter any issues accessing them, thank you!

EDB: https://www.dropbox.com/scl/fi/aw7w...oqevmdt708r7fswfqickp2oz&e=1&st=k9pnguiw&dl=0
E2K: https://www.dropbox.com/scl/fi/g584...vrz6g4l7jllfmi204dmu7dty&e=1&st=9m9pro5s&dl=0

 

[GJoeRMK]

If I have to guess, you did not mesh the membrane slab. Right?
Ok, looking at your etabs model, your slab is defined as a deck, and here the catch, in Etabs decks are always modeled as membrane, which mean it only support forces along its own plane, if you use a membrane element you need to provide it adequate support in Z direction.

I did the same mistakes when I started, so happy modeling.

 

[GJoeRMK]

For a beginner advice is to always look at CSI Analysis Reference.pdf