Estimating in Building Construction

(Barré) #1
Concrete 103

The bar length is 2 10 , which is derived by subtracting the cover-
age distance (22) from the footing width (3 2 ).


Continuous Footing Long Bars


The reinforcing for the foundation wall is found in virtually the same
fashion. From Figure 10.8, side A is 38 10 . Figure 10.21 specifies the


Add 10 percent for waste and lapUse 328 pounds

Total actual weight165 pounds133 pounds298 pounds

165 pounds

Total weight (pounds)158 lf1 .043 pounds per lf

Total bar length (lf )39.5¿4 bars158 lf

Total bar length (lf) 39 ¿ 6 – 4 bars

Length of long bars 39 ¿ 6 –

133 pounds

Total weight (pounds)127 .5 lf1 .043 pounds per lf

No. 5 bar weighs 1.043 pounds per lf

Total bar length (lf)45 bars2.833¿ per bar127.5 lf

Total bar length (lf )45 bars 2 ¿ 10 – per bar

Length of individual bars

Total bar length (lf )Number of bars


FIGURE 10.21.Footing Detail.

vertical bar spacing at 11 inches on center (o.c.). Therefore, the quan-
tity of vertical bars would be found in the following fashion:

Foundation Wall Vertical Bars (Side A)

Dowels

Add 5 percent for lap and wasteUse 142 pounds 

135 pounds

Total weight (pounds)129 feet1.043 pounds per foot

Total length of dowels 43 ¿ 3 ¿129 feet

Number of dowels 43

lf of each dowel 3 ¿

Add 10 percent for waste and lapUse 265 pounds

241 pounds

Total weight (pounds)231 lf1.043 pounds per lf

Total bar length (lf)38.5¿ 6 231 lf

Total bar length (lf ) 38 ¿ 6 –  6

Bar length 38 ¿ 10 –  4 –  38 ¿ 6 –

Number of barsSpaces 1 Use 6 bars

4.4 spacesuse 5

Number of horizontal spaces3 .667¿>0 .833¿

Number of horizontal spaces 3 ¿ 8 – >10 inches

Add 10 percent for waste and lapUse 164 pounds

1.043 pounds per lf149 pounds

Total weight (pounds)143 lf

Total bar length (lf )43 bars3 .33¿143 lf

Total bar length (lf )43 bars 3 ¿ 4 –

Total bar length (lf )Bar countLength of individual bars (ft)

Bar length 3 ¿ 8 –  4 –  3 ¿ 4 – bar length

Bar lengthWall heightBar coverage

Add 1 to get the number of barsUse 43 bars

Number of vertical bar spaces38.833¿>0.9167¿42 spaces

Number of vertical bar spaces 38 ¿ 10 – > 11 –

EXAMPLE 10-10 SLAB REINFORCING


If the reinforcing in a slab is done with sized deformed bars, the
bars are quantified in the exact manner as the footings and foun-
dation walls. Once again, the quantity of long and short bars
needs to be determined. Figure 10.22 is an example of how the
slab can be divided into unique areas so that the quantity of rein-
forcing bars can be determined. Using area A as an example, the
long bars will be (39 0   2 ) or 38 10 and the short bars would
be (25 4  2 ) or 25 2 .


Short bar spaces 39 ¿ 0 – > 12 –

Add 1 to convert to bar countUse 27 bars

Long bar spaces25.33¿> 1 ¿Use 26 spaces

Long bar spaces 25 ¿ 4 – > 12 –

Add 10 percent for lap and wasteUse 850 pounds

Total weight773 pounds

Total weight of bars (pounds)2,056 lf0.376 pounds per foot

Total length of bars (lf )1,049 lf1,007 lf2,056 lf

Total length of short bars25.16740 bars1,007 lf

Total length of short bars (lf ) 25 ¿ 2 – 40 bars

Total length of long bars (lf )38.833¿27 bars1,049 lf

Total length of long bars (lf ) 38 ¿ 10 – 27 bars

Add 1 to convert to bar countUse 40 bars

Short bar spaces 39 ¿> 1 ¿39 spaces
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