Hi,

**Aim:**To find out the compaction factor for the given fresh mix of concrete.

**Theory:**Workability of concrete is the ability/ease with which concrete can be mixed, transported and placed. This is a major factor which contributes to the other properties of concrete also. If concrete is workable enough then it can be compacted with less compacting effort.

So there is a relation between the amount of work required to compact a given fresh concrete and the work-ability of the concrete. This relation is well suited for the concrete of the low water cement ratio. Slump cone test is also used to find out the work-ability of the concrete but only recommended for the concrete of higher work-ability. For less workable concrete(having less water cement ratio), compaction is standardized by various standards.

**Apparatus:**Compaction factor apparatus/machine, weighing balance, cow/mixing tray.

**Procedure:**

**1.**Oil the inner sides of the top and bottom cone frustum.

**2.**Prepare a M15 concrete mix(1:2:4) using a water content of about 0.4-0.6 by weight of cement.

**3.**Fill the top cone frustum with the fresh mix of concrete and then open the gate and let the concrete fall on the second frustum.

**4.**Open the gate of second frustum and let it fall on the cylinder to fill up to top of cylinder.

**5.**Measure the weight of the cylinder filled with the concrete(partially compacted) and then empty this.

**6.**Again fill the cylinder with the same sample of the concrete but this time, do the compaction using the mechanical vibrator to do the compaction.

**7.**Again measure the weight of the cylinder filled with the concrete(Fully compacted).

**8.**Clean all the apparatus and put them at their places as before.

**Calculations:**

Let weight of the empty cylinder = W1

Let weight of the cylinder with the partially compacted concrete = W2

Let weight of the fully compacted(Using mechanical vibrator) concrete with cylinder = W3

*Compaction Factor = Weight of the partially compacted concrete/ Weight of the fully compacted concrete*

i.e., Compaction factor = (W2-W1)/(W3-W1)

**Result:**The compaction factor of the given fresh concrete mix is .....

(

*Note: Relation between the compaction factor and work-ability is that higher the compaction factor higher is the work-ability. Theoretical maximum value of the compaction factor can be 0.96 to 1.0*)
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