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CODE & SUBJECT : DCC 2042 – CONCRETE AND
BRICWORK
TITLE : SLUMP TEST
LECTURER’S NAME : PUAN HUSNA BINTI MAT SALLEH
KELAS : DKA1B
NAME
REGISTRATION NO.
MUHAMAD AKMAL BIN MOHAMAD SHARIF
03DKA16F2030
AINUNYASMINE BINTI HASLAN
03DKA16F2023
NIRANDOAL A/L CHENG
03DKA16F2029
NUR AIDA BINTI ZAINOL ABIDIN
03DKA16F2027
OBJECTIVE
To determine the workability or consistency of concrete mix prepared at the laboratory
or the construction site during the progress of the work. Concrete slump test is carried
out from batch to batch to check the uniform quality of concrete during construction.
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THEORY
Concrete is a mixture of sand and rock or similar inert material ( aggregates ) held
together by a cementing material. Usually the cementing material is Portland cement,
but sometimes binders such as asphalt or gypsum are used, in which case the concrete
may be called asphaltic concrete or gypsum concrete.
Properties of concrete are governed not only by the properties of its ingredients (
cement, water, sand, and coarse aggregate ) but also, to a great extent, by the relative
proportions of these ingredients. The proportions must be so selected as to produce a
concrete mixture of desired workability, strength, durability, and economy.
The most common aggregates are crushed stone, although cinders, blast – furnace
slag, burned shale, crushed brick, or other materials may be used because of
availability, or to alter such characteristics of the concrete such as workability, density,
appearance, or conductivity of heat or sound.
Slump is a relative measurement in concrete consistency. It is not an indicator of quality
of the material. The slump of a mix with the same aggregate, cement and water can
vary significantly by adding an admixture. The admixture does not reduce the quality of
the material.
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EQUIPMENT / APPARATUS / ROW MATERIAL
Iron Pan
Trowel
Slump Cone
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Tamping Rod ( 12 mm Diameter)
Measuring cylinder
Base
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PROCEDURE
STEP 1: SAMPLE PREPARATION
1. The quantity of concrete produced based on ratio of 1 : 2 : 4 which means 4 pail
of course aggregate, 2 pail of fine aggregate and 1 pail of cement.
2. The aggregates were in laboratory dry condition. Adjustment was made to the
concrete mix proportion to allow for adsorption of mix water by aggregates.
1. The pan and paddles were lightly moisturized.
2. Those material were added in order;
Coarse aggregate
Fine aggregate
Cement
3. The materials were mixed with 1000ml of water until the mixed blend well.
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3. The cement was spread evenly over the aggregates and continued mixed
4. 10. For ensuring homogeneity, the material was mixed by hand
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STEP 2 : TESTING
1. Clean the internal surface of the mould and apply oil.
2. Place the mould on a smooth horizontal non- porous base plate.
3. Fill the mould with the prepared concrete mix in 3 approximately equal layers.
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4. Tamp each layer with 25 strokes of the rounded end of the tamping rod in a
uniform manner over the cross section of the mould. For the subsequent layers,
the tamping should penetrate into the underlying layer.
5. Remove the excess concrete and level the surface with a trowel.
6. Clean away the mortar or water leaked out between the mould and the base
plate.
7. Raise the mould from the concrete immediately and slowly in vertical direction.
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8. Measure the slump as the difference between the height of the mould and that of
height point of the specimen being tested.
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RESULTS
Slump for the given sample is 50mm and the shape of the concrete slump is true slump.
DISCUSSION
From the performed experiment we came to know that our mean slump value was 50mm
which describes that it is True Slump and its workability is medium.The slumped concrete
takes various shapes and according to the profile of slumped concrete, the slump is
termed as true slump, shear slump or collapse slump. If a shear or collapse slump is
achieved, a fresh sample should be taken and the test repeated. A collapse slump is an
indication that the mix is too wet. A change in slump height would demonstrate an
undesired change in the ratio of the concrete ingredients; the proportions of the
ingredients are then adjusted to keep a concrete batch consistent. This homogeneity
improves the quality and structural integrity of the cured concrete.
Only a true slump is of any use in the test. A collapse slump will generally mean that the
mix is too wet or that it is a high workability mix, for which the slump test is not
appropriate. Very dry mixes having slump 0 – 25 mm are typically used in road making,
low workability mixes having slump 10 – 40 mm are typically used for foundations with
light reinforcement, medium workability mixes with slump 50 – 90 mm, are typically
used for normal reinforced concrete placed with vibration, high workability concrete with
slump > 100 mm is typically used where reinforcing has tight spacing, and/or the
concrete has to flow a great distance.
Limitations of the slump test
The slump test is suitable for slumps of medium to high workabiity, slump in the range
of 5 – 260 mm, the test fails to determine the difference in workability in stiff mixes
which have zero slump, or for wet mixes that give a collapse slump. It is limited to
concrete formed of aggregates of less than 38 mm (1.5 inch).
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CONCLUSION
The concrete slump test measures the consistency of fresh concrete before it sets. It is
performed to check the workability of freshly made concrete, and therefore the ease
with which concrete flows. It can also be used as an indicator of an improperly mixed
batch. The test is popular due to the simplicity of apparatus used and simple procedure.
The slump test is used to ensure uniformity for different loads of concrete under field
conditions.
A separate test, known as the flow table, or slump-flow, test, is used for concrete that is
too fluid (workable) to be measured using the standard slump test, because the
concrete will not retain its shape when the cone is removed.
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