Unexpected Mz in beams

[Anonymous]

Hi friends

I am calculating a steel structure and i am getting unexpected Mz in some members. See capture below

As you see this happens in both slabs. Can anyone help me?

Model attached

Regards,

[Rafacascudo]

There´s a rigid link  and acts especially for load 6 Wx transfering the concentrate load to the region where the MZ occurs

If it´s a wind load set it on the panel exterior edges/beams on the facade and let the diaphragm distribute the load more evenly

[Anonymous]

Thank you for your answer my friend

But see for example combo 39 (It doesnt include Wx) and there is high Mz too. Maybe is due to Tx and Ty (accidental torsional moments). What do you think?

So rigid link seems to be the problem. But how do i include that nodes (720 and 717) in the diaphragms to get a good behavior of the structure?

Thakns in advance

[Simau]

hI @Anonymous

Try horizintal bracings on the slabs instead of rigid links.

Why There is no release on secondary bars?

[Rafacascudo · Accepted solution]

Include nodes 717 and 720 manually on the corresponding Diaphragm rigid link . Look below

   Delete the rigid links you created and let the diaphragm do the job .

   The analysis will give you and instability type 2 for nodes 717 and 720 , but it doesn´t matter as they are isolated nodes that are  there to just load the strucutre through a rigid link.

[Anonymous]

Thank you my friend @Rafacascudo