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[binaya shahi]

I have modeled and designed a rcc building in etabs 2015. But i have many doubts regarding the steel area of columns etabs has calculated. Please review my model attached here with.

It has 3 bays(4 gridlines) in x direction and 2 bays(3 gridlines in y direction).
all grid lines are 14' apart forming about 13'x 13' room.
total no of room=6

NO. of stories:4
story height:10'
edge and cornor columns: 12"x12" m20 concrete, Fe500 rebar
inner columns: 14"x14" m20 concrete, Fe500 rebar
slab: 4.5" m20

dead load: program calculated
live load: 3kN/m^2 on all slabs
floor finish: 1KN as superdead on all slabs
wall load: 10kN on all beams except on the 4th story which has 4KN
eq load: IS code
wind load: IS code

I haven't applied modifier to  section properties of beam, column and slab as i read somewhere it isn't required. I don't know if it valid for just etabs 2015 or in general. Please make me clear about this concept of applying modifier to represent cracked section. Is it mandatory?

assigned the default diaphragm D1(rigid) for all slabs.
mass source is also the default one (MsSrc1). I didn't touched that one.

Please review my model and bmp image of steel area result. and quench my doubts below! Thank you so much in advance.

The reinforcement area for edge columns in story-2 is about 2 times that of story 3.

The reinforcement area(2439mm^2 ie. about 8 no. of 20mm bars) for the inner columns in story1 is about 2.5 times that of story2.

are these values normal?
or am i doing something  wrong or missing something?