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Different concrete strengths for columns and floor system

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Refer to ACI Code Section 10.15 for "Transmission of column loads
through floor system" ,
which says that where the column concrete strength does not exceed the
floor concrete
strength by more than 40 percent, no special precautions need be taken.
Now, consider a case of  a mutistoried building periphery  column 9"x36"
of  5000 psi
concrete framed by  9"x48" deep spandrel beam of  4000 psi  concrete,
along the column length.
The column upto the bottom of the beam is cast with 5000 psi concrete
whereas the column portion cosisting of the 48" deep beam is cast with
4000 psi concrete, as is cutomary. Now my question is:
Is it reasonable
to apply  the above ACI clause to this situation and do nothing about
the low concrete strength for the 48" portion of column, since
the concrete strength
ratio is  less than 1.4 ? Any comments would be welcome.

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