The document discusses the compaction factor test for measuring the workability of concrete. The compaction factor test determines workability by measuring the compaction achieved when concrete falls freely from a hopper into a cylinder. A compaction factor of 0.75 to 0.8 is recommended, according to IS 456-2000 standards. The test involves partially filling a cylinder by simply allowing the concrete to fall in, then fully compacting it with a rod and calculating the ratio of the weights.

1. PREPARED BY : -
Dushyant Chhatrola
CONCRETE TECHNOLOGY
(2140608)
MEASUREMENT OF WORKABILITY
BY COMPACTION FACTOR TEST

2. Measurement of Workability
• Workability of concrete is a composite property.
• Various tests are available for measuring the
workability of fresh concrete, but none of them is
wholly satisfactory.
• Each test measures only a particular aspect of it.
• There is really no unique method which measures
the workability of concrete to bring out its full
meaning.

3. Measurement of Workability
• The following tests are commonly used to measure workability.
- Slump test
- Compaction factor test
- Flow test
- Vee bee test
- Kelly ball test

5. Compaction Factor Test
• Slump cone test does not give good results in case of
stiff or harsh concrete. Hence the compaction factor
test is used.
• The compaction factor test gives the behavior of fresh
concrete under the action of external force.
• In this test, the compaction achieved through a free
fall of concrete determines its workability.

6. Compaction Factor Test
• It is more accurate than slump test for concrete mixes and
value of compaction factor of 0.75 to 0.8 is suggested as
per IS 456-2000.
• It is not suitable for concrete of very low workability of
0.7 or below.

7. Compaction Factor Appartus

8. Compaction Factor Test Procedure
• The concrete sample is placed in the upper hopper.
• Then the door of hopper is opened. The sample drops into lower hopper
filling it to overflowing.
• The trap door of the lower hopper is then opened and the sample falls
into the cylinder which is also filled to overflowing.

9. Compaction Factor Test Procedure
• The surplus concrete is removed from the top of the
cylinder with the help of a trowel.
• The outside surface of cylinder is wiped and cleaned.
• The cylinder is then weighed and it is recorded as weight of
partially compacted concrete.

10. Compaction Factor Test Procedure
• The cylinder is again filled with concrete in layers not exceeding
50 mm in thickness. Each layer is fully compacted with tamping
rod.
• The cylinder is again weighed after wiping and cleaning the
outside surface of cylinder. This weight is recorded as the weight
of fully compacted concrete.

11. Compaction Factor Test Procedure
• The compacting factor is then calculated from the formula:
• 𝑪𝒐𝒎𝒑𝒂𝒄𝒕𝒊𝒏𝒈 𝒇𝒂𝒄𝒕𝒐𝒓 =
𝒘𝒆𝒊𝒈𝒉𝒕 𝒐𝒇 𝒑𝒂𝒓𝒕𝒊𝒂𝒍𝒍𝒚 𝒄𝒐𝒎𝒑𝒂𝒄𝒕𝒆𝒅 𝒄𝒐𝒏𝒄𝒓𝒆t𝒆
𝒘𝒆𝒊𝒈𝒉𝒕 𝒐𝒇 𝒇𝒖𝒍𝒍𝒚 𝒄𝒐𝒎𝒑𝒂𝒄𝒕𝒆𝒅 𝒄𝒐𝒏𝒄𝒓𝒆𝒕𝒆

12. Recommended values