For Example, dimension of a column is 1200/1400/1600mm sagging moment at column center is much greater than column face (which is 600/700/800mm away from center of column).
In the above snap, moment at center of column(1200mm*1200mm) is ~6140kN-m. If we move to face of column moment is ~5100 kN-m.
So why RCDC designs a beam for 6140kN-m instead of ~5100 kN-m.
Please refer below link for solution.
How to calculate reinforcement of beam at face of column in RCDC? - RAM | STAAD | ADINA Wiki - RAM | STAAD | ADINA - Bentley Communities