The above are to design steel requirments in a slab.
However to calculate amount of steel in a slab u simply need
drawings. A simple assumtion of 10d (i.e:- 10 * diameter )
is ok for bent up calculations.
practically for slabs steel is caluclated in this manner:
for a given room of size 6.5x5.2,first we provide main reinforcement in shorter span and distribution steel in longer span.so,here we provide main reinforcement in breadth side(i.e... 5.2m side).and distribution in other side.so,we preapre a tabular form for a given spacing and dia of steel.
then we caluclate no of bars.therefore,no.of bars=length/spacing.next bar length is caluclated according to sections given.i mean there will be given different sections for rooms and given a brief diagram for steel placing.so both top mat and bottom mat we caluclate the bar length.for both main and distribution steel.to find qty=bar lengthxno.of barsx((dxd)/162)xunit weight of steel.here note that length and bar lengths are different.length means room size and bar length means length of bar with projections inside the room.
l spacing no dia barlength qty
top mat 6.5 0.15 44 10 this is acc to
bottom mat 6.5 0.15 44 10 5.2+0.23+0.2
top mat 5.2 0.2 26 8 6.5+0.23+0.2
bottom mat = 0.2 8 6.5+0.23+0.2
=same as main steel top mat
here 0.23 is wall thickness.so both sides 0.23 means we take one 0.23 and add bending value as 0.2 in most cases
we cant calculat the steel how much we used on per sq.ft
1) it depend on structur for exam:-in G+7 we used 7kg to 8kg ,inG+4 we used 2.5kg to4kg, as in colleg,masjed,tempul we used 10 to 14kg
As one more importan it depen on the field (soiel)
It have maney resion
We the ferfet formula how we can make concret accourding to satwation on the field. But for steel desing we have work accourding to the fiel
it will be depend on the area. just calculate the area then
spacing.,.,after than total length/ spacing = no of bar. use
the formula d*d/162 = total steel waight per meter.,.,.
multiply total to total length= total steel in the rcc slab
Providing and fixing in position Tor steel to footings,
foundation, slabs, beams, columns, canopies, stair case,
newels, chajjas, lintels, etc. including cutting, bending,
hooking the bars, binding with wires. give me the rate M.ton.