Grade Beam Modelling with moment Frame

Hi Team,

I have a steel structure having the LFRS as steel moment frames.

Now I have started modelling the grade beams as per the RAM SS guidelines, but I have the following queries :

• It says that the supporting short column should be pinned at top and fixed at bottom but does not specify the fixity condition of frame column above. Please specify.    
• If I simply do the, supporting short column to be pinned at top and fixed at bottom, and provide fixed base for frame column. The design is showing that columns are failing in standard checks having extreme DCR.
• If I simply do the, supporting short column to be pinned at top and fixed at bottom, and provide pinned base for frame column, it doubles the drift.

Please help me to resolve this issue.

I will be sending the RAM model with a name "20220930_MI_RAM Model with Grade Beam".

Thanks & regards,