YIELD MAN HOURS FOR REINFORCED CONCRETE AT CONSTRUCTION JOBS

To make a quick estimate of the man hours needed for the execution of works of Reinforced Concrete, we must add the following times

1-Time to Manufacture and Filling of Concrete
For this task and for the case that the concrete is manufactured by hand and the work is at floor level, we take a conservative 8-hour time man x m3 for manufacturing and filling of the concrete.
If we worked with a Concrete Plant Works installed with trucks mixer (in optimum conditions) should compute 1.5 hours per m3


2-Time for form-work
First we must know the m2 of form-work per m3 of concrete wet (m2 form work / m3 of concrete, which we call "A"), this value is variable, depending on the structure. Then we must know the m2 of form-work that are manufactured and placed per hour. Shuttering for whose panels are made once and then reused, would have an output of 0.80 m2 of form-work per hour, which we call " B "
If the form-work should be made whenever a structure is built, it would have an output of 0.35 m2 of form-work per hour will call "C" .. then dividing the value "A" to "B" or " C "as appropriate and so we get the time of form work

3- Time cutting, folding and assembly of steel reinforcement
In this case we need to know the number of Kilograms of iron per m3 of concrete, which we call "D" and then divide by the kilograms of iron that is cut, folded and assembled per hour, this task has a throughput of 10 kg per hour to call "E" ... by dividing "D" "E" we have the Time of the steel armature

4-We need add another time at this work-variable time
Time-motion work in Materials
-Times by curing
-Stripping and cleaning panels
-Time for controls
-Time by excavation or soil movement
-Time for vertical movement of Concrete

Example

If we build a reinforced concrete wall with a height of a 1metro and a thickness of 0.20 m, with an amount of 90 kg of iron per m3 of concrete, the number of hours that would require for this work, would be the next

Time manufacturing and filling of Concrete = 8h x m3

Time for Form-work
(Here, the panels are manufactured and then refuse)
M2 form-work/m3 Concrete, ie A = 10m2/m3
The formwork refuse .. Then B = 0.80 m2 per hour
Dividing A/B = 12.50 h x m3

Time for the Steel Armor
D = 90 kg x m3 of concrete and E = 10 kg per hour ... then D / E =9h x m3

Estimated Time to make this structure = 8+12,50+9=29.5 hours x m3

In this value you must add the variable time accord with the type of work(item 4)