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[binaya shahi]

This is my first attempt in design of a rcc building in etabs.


But i have some doubts regarding steel area. The steel area in columns in the first floor(story4) is three times of that in second floor(story5) for grid 1 and 3, and its about 2 times for grid-2. see steel area elevation grid 1-1,2-2,3-3 attached herewith.

Another problem is that area of steel is too high for columns. For example its 3418mm^2 for one of the colums in ground floor(story-3) grid 2-2. That would be 11 number of 20mm bars or 17 no of 16 mm rebars.

I want to know whether these results are normal or its unusual? Please somebody help me to interpret and understand  these results.

Another thing to notice is that beams have low steel percentage.
Material for all sections M20 concrete and Fe500 steel.
All beams 9"x13".
All interior columns 14"x14".
All edge and cornor column 12"x12".
slabs in first, second and third floor 4.5" thick.

No. of floors: 4
No. of stories in etabs mode: 6 including (one about 2' high story between plinth tie and foundation tie, another about 6' high story in between bottom of footing and foundation tie)

No of gridlines along x-axis: 4(14' apart)
No. of grid lines along y axis: 2(14' apart)

loads applied:
shell load 3kN live load to slabs
               2kn finishes as superdead load to slabs

wall load 8 kn/m to beams in ground, first, second and third floor to beams.(for brick masonary 5 inch wide and 10ft hing)

seismic load as per IS code(supposed to be calculated by program itself)
wind load as per IS code(supposed to be calculated by program itself)
dead load (supposed to be calculated by program itself)

load combination: program generated as per is code.
etabs file along with picture of the steel area output are attached herewith.