I completed the modelling of the building in two models; one with concrete parts only and other with only the top floor modelled.
I exported the support reactions of column at the base to excel and calculated the maximum value of each value Fx, Fy, Fz, Mx, My and Mz for each joint at the bottom using Excel Macro.
Then I input those values in the joints of model with concrete part only at the top of story 2.
The results seem quite satisfactory.
Can I do it like I mentioned above?