I changed the mesh. It seems normal now. However, I still have the same problem!
I kindly ask you to review my questions again and give your comments. Many thanks in advance.
1. I found that M-S connections was not a root of the problem. I changed mesh to compatible in problematic joint and got the same results. However, please comments whether it is possible to use MS condition while connecting incompatible mesh frame-to-frame and shell-to-frame.
3. Beams elements are connecred with MS contact (see Figure 2 from message #7). Is this correct? Is there a need to make mesh consistent?
4. Beams are connected to walls and slabs with MS as well. Is this approach correct? (Figure 3 from message #7)
5. Would you please review my model and advice what can be a problem with convergency in problematic nodes? (FT4_v12.gid.rar - GiD model without results). Please note that in problematic beams stresses in rebars are very low (less than 250 MPa) and failure should not occur (see FT4_v12.avi from the link below).
6. Cracks in shells and frames are shown through the full height of the element (see CRACKS.PNG from the link below). It looks totally enormous from structural point of view. Is there a modeling mistake or is it a symbolic representation of ATENA?
https://drive.google.com/open?id=13xNmg … 4Drw1bUqw4