Goodmorning everyone

I have a problem with a planar model of steel MRF .

In particular, in addition to the normal MRF structure, I introduced the leaning columns where I applied: the concentrated masses, the incremental forces (for a PushOver analysis) and the concentrated vertical forces (to take into account the gravity loads for the P-delta effects). The model workswell with the one exception for P-delta effects. In fact, there is no degradation structural capacity curve (Base shear vs top displacement), moreover also changing the level of the concentrated force, the results seem to be insensitive.

Do you have any idea what could be the modeling error? For an easier understanding of the problem, attached you will find the model

Thank you

Roberto

P.S. I have already set the geometric nonlinearity.

Dropbox Link:

https://www.dropbox.com/s/aougvq599c2a8 ... r.spf?dl=0