Civil_Engineering_Materials_FULL_Lab_Rep.pdf

GROUP 15 – CEM Laboratory
LABORATORY 1,2 AND 3
CIVIL ENGINEERING MATERIALS
(VDB 2013)
GROUP MEMBERS (GROUP 15)
1 Afnan Munir bin Mohd Khairi 23779
2 Ashikin Mastura binti Amirudin 23859
3 Thooy Kok Yaw 23876
4 Muhammad Haziq Hazim Bin Abd Halim 23901
5 Mohammed Jehad Kishawi 24791
6 Nur Ain Syafiqah binti Abdul Halim 25598

GROUP
MEMBERS

CONCRETE MIXING
Date of laboratory: 4th October 2017
MIXING AND SAMPLING FRESH CONCRETE
OBJECTIVE
To mix and sample fresh concrete in the laboratory.
INTRODUCTION
Concrete is a hardened building material created by combining a chemically inert mineral
aggregate (usually sand, gravel, or crushed stone), a binder (cement), chemical additives, and
water. The most crucial step in this process is to determine the proportions of ingredients that
will make up the concrete.
There are many variables to consider during the calculations. Some of them are cement type,
aggregate size and type, amount of water, and mineral and chemical admixtures. While a good
mix design can still result in inadequate or poor-quality concrete if it is not executed correctly, a
bad mix design will of course always give poor results. Therefore, before the process of mixing,
calculations of proportion of material must be done.
In the industry, the process of producing concrete starts with batching which means weighing of
all the materials needed to make the concrete. This is followed by mixing, transporting, placing,
compaction and curing. In this laboratory session, we did a small-scale mixing of concrete. All the
processes were done but in small scale, which was up to six small cubes of concrete. For our
concrete, the expected strength is 55 MPa.
APPARATUS
A non-porous timber or metal platform, a pair of shovels, a steel hand scoop, measuring
cylinder and a small concrete mixer, weighing machine, 6 cube molds.
PROCEDURE

1. The quantity of cement, sand and coarse aggregate were weighed according to the ratio
that was calculated earlier. (appendix 1)
2. Sand and coarse aggregate were put into the mixing machine and was mixed for 1 minute.
3. Half of water needed were added to the mixer, and was mixed for 1 minute. Then it was
left for 8 minutes.
4. Then, the cement was added to the mixer and was mixed for 1 minute.
5. The remaining volume of water was added and was mixed for 1 minute.
6. Then, the mixture was hand mixed to ensure homogeneity.
7. Three tests of workability were carried out while the concrete was hand-mixed to make
sure it will not harden.
8. After done with workability test, the concrete was then filled into 6 cube mould. Then it
was put on a vibrating machine to compact it.
9. It was then left for 24 hours.
10. After 24 hours, the concrete cubes were then demolded and was put inside a tank full of
water in the curing room for curing process.
Precaution
1. The room temperature should be approximately 25-27°C.
2. Make sure that fine and aggregate are dry. If they are wet find the content of the
aggregates to determine the quality of water required.

RESULTS/OBSERVATIONS
Figure 1 After machine mixing
Before the mixing, all the materials were very segregated. We understood the steps of mixing in
the lab manual before starting the experiment.
After the mixing, the mixture become more homogenous, and the color was darker compared to
before mixing. The mixture became very thick and quite difficult to hand-mix them. From the
Figure 1, we can obvious that most of the aggregates were well coated by the cement paste with
the help of water and this indicate that all the materials were well mixed. Then, this was followed
by hand-mixing to ensure the homogeneity of mixture so that the paste is encapsulating the
aggregates hence the required concrete can be made.
DISCUSSION
(Afnan Munir Bin Mohd Khairi 23779)
Concrete mix design is a process of selecting suitable ingredients of concrete and determining
their relative quantities. Before conducting the experiment, some calculation have been made
for determining the target mean strength, water/cement ratio, free water content, cement
content, fine and coarse aggregates. All the values obtained according to the specified strength
given which is 55 MPA.

Some preparations like we have to dry the fine and coarse aggregates one day before for ensuring
that there is no excess water in the concrete mixing. After measuring all the component according
to the value calculated, we started to mix the fine and coarse aggregates with half of water the
followed by half of cement. The mixture was mixed for a few minutes and then another half of
water and cement were added. This step must be followed in order to make sure that all
aggregates will be well coated by the cement so that the concrete will be more efficient due to
compression.
To achieve a higher strength concrete (55 MPa), the water-cement ratio must be low, but this
will reduce the workability. Thus, a lot of effort needed here while “hand mixing” to prevent the
hardening.
Reliability
1. The fine aggregate are not fully dried
2. The fresh concrete were hardened too fast due to lack of hand mixing.
3. The weighing scale was not set to zero while weighing.
Modification
1. Make sure that the fine and aggregate is fully dried by exposing it to the sunlight.
2. Make sure the fresh concrete is mixed frequently.
3. Make sure the weighing is set to zero.
(Ashikin Mastura 23859)
By carrying out this experiment, we were able to determine the production of concrete mixing.
the first step into making the concrete is batching of materials. We had to measure and separate
the ingredients so that it will be ready for the next step. This consists of fine aggregates, coarse
aggregates, water and cement. Next step in to the procedure is the mixing of materials. Sand and
coarse aggregates were added first followed by half volume of the water. This will ensure the
aggregates are coated, into a blend all ingredients of concrete into a uniform mass. then, cement
was added into the mixer creating a bind between water and aggregates that was initially added.
As mixing continues, we observed that the colour turned from gray to a deep gray colour. the last

portion of cement was then added with the other half of the water to ensure homogeneity. Next
step is transporting from the mechanical mixer to the wheelbarrow and continuing mixing
manually. The fresh concrete needed to achieve a 55 MPa of concrete strength. Hence, the water-
cement ratio was carefully calculated to ensure target can be aimed.
(By: Thooy Kok Yaw 23876)
From this experiment, we were able to know and learn the steps of concrete mixing.
Before starting the experiment, we were done for the batching of materials as we did the
measurement of all materials used in production of concrete. Furthermore, fine aggregate such
as sand was dried one day before the experiment start to ensure there is no excess water amount
in the mixing.
Sand and coarse aggregates were added in the mixer first followed by half volume of the
water. This is to ensure the aggregates were well coated by the water. Then, cement was added
into the mixer and coated with aggregates easily due to the water that was already on the
aggregates that acted as a ‘glue’. After that, most of the surface of aggregates were coated with
cement paste as the colour of the mixing became darker and darker. After the addition of cement,
another half volume of water was added in the mixer to ensure a homogeneity and of mixing.
The fresh concrete after mixing was poured into a wheelbarrow then followed by hand-
mixing to prevent the fresh concrete from setting too fast. The lower the water-cement ratio, the
higher the strength of concrete but the lower the workability of concrete. To reach the concrete
strength requirement which is 55 Mpa, more force was needed from us to do the hand-mixing
due to the low water-cement ratio.
Reliability
1. The fine aggregates such as sand was not dried completely before weighing and mixing
and causing a higher water content in it.
2. Make sure the mixing machine was free from contamination of impurities.

3. Not all the aggregates were capsulated by the cement paste due to lesser time of mixing.
Modification
1. Expose the fine aggregate such as sand under the sunlight one day before the experiment
start to ensure it is dry enough.
2. Clean the mixing machine with water and let it dry before placing the materials in it for
mixing.
3. Make sure the procedure of mixing of mixtures is correct by mixing with the specific time.
(By Muhammad Haziq Hazim Bin Abd Halim, 23901)
From the experiment conducted we have learned the correct steps on how to make concrete
based on the strength given. There are five components needed in making concrete which are
sand, fine aggregates, coarse aggregates, water and cement. Concrete mix design is a process of
selecting suitable ingredients of concrete and determining their relative quantities. Before
conducting the experiment, some calculation has been made for determining the target mean
strength, water/cement ratio, free water content, cement content, fine and coarse aggregates.
All the values obtained according to the specified strength given which is 55 MPA.
Some preparations like we have to dry the fine and coarse aggregates one day before for ensuring
that there is no excess water in the concrete mixing. After measuring all the component according
to the value calculated, we started to mix the fine and coarse aggregates with half of water the
followed by half of cement. The mixture was mixed for a few minutes and then another half of
water and cement were added. This step must be followed in order to make sure that all
aggregates will be well coated by the cement so that the concrete will be more efficient due to
compression.
After mixing, we can see that all aggregates have been well coated, and the color of cement
turned to be darker rather than before. The fresh concrete was poured in the wheelbarrow and
we have to hand mix the paste to prevent it from setting too fast. We have found that the paste

was quite hard to mix by hand because the water cement ratio is low in order for the concrete to
achieve the target strength. So, from that we can assumed the workability of the concrete is low
before the tests will be perform on the concrete.
Reliability
1. The measurement of the fine and coarse aggregates was not accurate due to the excess
water contain.
2. Zero button on the weighing scale was not calibrated correctly.
3. The paste found to settle too fast.
Modification
1. We have to dry the fine and coarse aggregates under the sun at least one day before
2. We have to make sure that the scale was set to zero before the measurement taken.
3. Everyone have to take part in the hand mixing as it need to be more often mixed.
(By: Mohammed Jehad Kishawi 24791)
Before we started the experiment, we made sure that we know the steps and how to conduct it,
as first we need to do the batching which is taking note of the materials that will be used with its
amount. Then, the fine aggregate was dried a day before conducting the experiment to make
sure the percentage of water in aggregate is low or even removed.
Once the water aggregate is fully dried we proceed to mixing, were here we added the coarse
and fine aggregates in the mixer with ½ the volume of our current water for 1 minute, then leave
it for 8 minutes so flocculation can take place. Then, OPC were added to the mixer with the
remaining water and some admixtures if needed and mixed for 1 minute, as the color goes darker
it indicates that the aggregates surface is coated by the cement, after we are done mixing, now

we transport the fresh mixed concrete in site, while transporting it using the wheelbarrow we
did hand mixing to prevent it from hardening.
To achieve a higher strength concrete (55 MPa), the water-cement ratio must be low, but this
will reduce the workability. Thus, a lot of effort needed here while “hand mixing” to prevent the
hardening.
Reliability
1. The fine aggregate is not fully dried
2. The fresh concrete was hardened too fast due to lack of hand mixing.
3. The weighing scale was not set to zero while weighing.
Modification
1. Make sure that the fine and aggregate is fully dried by exposing it to the sunlight.
2. Make sure the fresh concrete is mixed frequently.
3. Make sure the weighing is set to zero.
(Nur Ain Syafiqah binti Abdul Halim, 25598)
As concrete is made up of different component which are water, coarse and fine aggregate and
also cement, mixing has to be done to make sure all substances are mixed well together. The
objective of mixing is to coat surface of aggregate with cement mix and water is needed for
hydration process to occur.
After the mixing process, we can see that all the substances are well mixed and homogenous,
compared to before mixing. All the aggregate has been coated with cement mix. This is to make
sure the concrete will function as it should be, which is to resist compression.
The colour is darker than before as the cement has reacted with water, therefore it appears
darker than before mixing. The mixture also become a thick paste and quite difficult to hand-mix
it as the water cement ratio is low. This is because the strength expected for the concrete mix is
quite high which is 55 MPa. Therefore, we can expect that the workability will be low.

Concrete mixing is very important process in construction as most of buildings nowadays is made
up of concrete, and usually is reinforced with steel. But the most important step in mixing is the
compaction as it prevents void in the concrete. Presence of void will affect the buildings greatly.
Curing which was the last step is to make sure the hydration to continue so that the concrete will
achieve its greatest strength. In the big scale, usually contractor will put gunny sack at the
concrete and sprinkle with water to cure the concrete.
Reliability
1. Water might present in aggregate making the weighing inaccurate.
2. Impurities in the container while doing the batching process might affect the weight of
the materials when it was weighed.
Modification
1. Dry the aggregate under the sun before weighing.
2. Make sure container to do batching process is cleaned before weighing to avoid any
impurities or inaccuracy.
CONCLUSION
As a conclusion, from this experiment we have learnt on how to do concrete mixing. We can say
that the objective, which is to mix and sample fresh concrete in the laboratory is achieved. Other
than that, we also learnt the importance of each steps of production of concrete, by doing it in
small scale in the laboratory.

SLUMP TEST - TEST FOR WORKABILITY
OBJECTIVE
To measure the workability of a sample from a batch of fresh concrete of a given.
INTRODUCTION/THEORY
Slump is a measure of the consistency of fresh which is measured by carry out the concrete slump
test. 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 slump test is used to ensure uniformity for different loads of concrete under field conditions.
The measurement of the workability of fresh concrete is important in assessing the practicality
of compacting the mix and in maintaining consistency throughout the job.
In this test, we have set the slump of the concrete to be 100mm. The concrete is filled into the
mould and lifted to measure the slump. The difference between height of mould to height of the
concrete after the mould is lifted is the measure of slump. In addition to this, there are few type
of slumps as shown in (figure 1).
Figure 1 Type of slump

APPARATUS
Truncated conical mould 100mm in diameter at the top, 200mm at bottom and 300mm high,
with a steel tamping rod (16mm diameter & 600mm long), rounded at one end, a scoop, a steel
ruler and a steel trowel.
PROCEDURE
1. The inside of the mold was cleaned and was placed on a hard, flat and non-absorbent
surface.
2. Some sample was taken out from the fresh concrete mix.
3. The mold was filled with fresh concrete till one fourth of the mold and the layer was
rodded 25 times with rounded end of steel rod. The rodding was make sure to pass
through the high of each layer.
4. Step 3 was repeated until the mold is fill until the top.
5. After the top layer has been rodded, the surface of the concrete was struck off with a
trowel to level up with the top of the mold.
6. The spillage of concrete spillage around the base of the mold was cleaned away.
7. The mold was carefully and slowly lifted vertically from the concrete. The mold was
inverted and placed next to the molded concrete. The concrete slumped.
8. The rod was placed across the top of the mold.
9. The difference between height of slumped concrete and the mold was measured. By using
steel ruler, the slump of top concrete to underside of the rod was measured.
10. The difference was recorded.
Figure 2 Measuring difference in height for the slump

RESULTS
The difference in height = 10mm
DISCUSSION
(AFNAN MUNIR BIN MOHD KHAIRI 23779)
Concrete slump test is to determine the workability or consistency of concrete mix prepared at
the laboratory or the construction site during the progress of the work. Generally concrete slump
value is used to find the workability, which indicates water-cement ratio, but there are various
factors including properties of materials, mixing methods, dosage and admixtures.
During the lab session, we take an amount of concrete and fill it into the frustum of steel cone in
three layers. Then, we are required to hand tap the concrete by tampering 25 times by using a
steel rod. After the steel cone is filled and tampered, we turn the cone upside down and start to
measure the slump as downward movement of concrete.
Based on the result, we get 10 mm of slump which can be called true slump. As we have high
number of target strength which is 55 Mpa,we need to use low content of water cement
ratio.Thus,this result in low value in our slump test.
Reliability
1. Slump test should not be carried out if the aggregates used is 40 mm.
2. Slump test won’t suit for the concrete mixture that is very dry concrete because it doesn’t
show the differences in heights.
3. Parallax error might be done by the person in charge during taking the measurement of
the components.
4. Concrete might not be thumped perfectly as the force applied each time released the rod
was not same.
Modification
1. We have to make sure that the aggregates used were below than 40 mm.

2. We should performed a relevant calculations so that slump test can be carried out for
the concrete.
3. The person in charge must place the eyes perpendicular to the scale to get the accurate
result.
4. We have to make sure that the rod must be released at approximately at the same
height to obtain same forces for every thumping process.
(Ashikin Mastura, 23859)
Concrete slump test is to determine the workability or consistency of concrete mix prepared
during lab session 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. It can also be known as
measuring consistency to determine rapidly whether a concrete batch should be accepted or
rejected.
During lab session, a sum of concrete was filled into the frustum of steel cone in three layers. The
concrete then was hand tap in each layer by tampering as much as 25 times (using a steel rod).
After filling three layers, the cone was lifted and then rotate to 180 degrees (upside down). This
is to measure the slump as downwards movement of concrete.
From obtaining result, there is a slight slump in our mixture. This indicates the difference of height
of the frustum with the height of concrete. The difference is 10 mm and the type of slump
determined was a true slump. This means that the general drop of the concrete mass is evenly
all around without disintegration. Although, we can also conclude that the workability of the
concrete is low due to low optimization of water-cement ratio.

(By Thooy Kok Yaw 23876)
From this experiment, we were able to learn that the concrete slump test is a
measurement of fresh concrete consistency before it sets. This test was performed to check the
workability of freshly made concrete and therefore the ease with which concrete flows.
After the removing of truncated conical mould, we were able to get a true slump with a
10 mm difference between height of slumped concrete and the mold. The fresh concrete was
slumped due to the water-cement ratio and flow down by its own weight and this also know as
slumping. The higher the water-cement ratio, the higher the workability and the bigger the
difference of slump. Since the targeted strength of our concrete is 55 MPa, only a low water-
cement ratio is needed. Therefore, due to a lower water-cement ratio, our fresh concrete
categorize under true slump as it is a low workability fresh concrete.
Fresh concrete was well compacted each layers in the mould by using rounded end steel
rod for 25 times. This is to ensure that the fresh concrete obtain a higher cohesive and reduce
the risk of segregation. Slump test is very convenient as the procedure is simple and easy than
any other workability test. Besides, it is inexpensive and portable apparatus that can be
performed at the construction site as well as in the laboratory.
Reliability
1. The truncated conical mould was contaminated inside by some suspended solid.
2. The fresh concrete was not compacted for each layers or the amount of compaction was
less than 25 times.
3. The compaction force on the fresh concrete at each layer were not applied uniformly.
4. Parallax error happened when taking the difference between height of slumped concrete
and the mold.
Modification
1. Wash the truncated conical mould and let it dry before starting the experiment
2. Make sure the fresh concrete was inserted one fourth of truncated conical mould each
time and compact the fresh concrete well with 25 times by using rounded end steel rod.

3. Apply the same compaction force on the fresh concrete at the same height.
4. Make sure the eyes of observer is perpendicular to the scale of meter ruler to obtain a
more reliable result.
( By Muhammad Haziq Hazim Bin Abd Halim, 23901)
Slump test is carried out to measure the consistency of concrete which indicates the workability
of concrete. Consistency refers to the ability of the concrete to flow without the segregation of
ingredients. The more consistent of the concrete mix, the concrete is considered as stiff while
the less consistent of the concrete mix, the concrete is considered as soft. The major factor that
affect the consistency and workability of concrete is water cement ratio but there are more minor
factor that affect the workability of concrete which are the size, shape, grading, surface texture
of aggregates and also the use of admixture.
From the slump test conducted, the difference of the slump is 10 mm which indicates it as true
slump as concrete slumps evenly and forms a shape same as a mould. Based on the result, we
can say that our concrete mixture is stiff because of the workability is low. Less amount of water
cement ratio is the one of major cause of having low consistency but if there is too much amount
of water cement ratio, bleeding can take place. So by doing slump test to the concrete, we can
obtain adequate amount of water cement ratio for a specific strength. Our concrete mixture is
still can be accepted as low water cement ratio is suitable for a quite high target strength which
is 55 MPA.
Although it is very easy to perform this method. But it is not suitable for very wet or very dry
concrete. It does not measure all factors contributing to workability and concrete placeability.
This test often be used in construction industry as a control test and gives an indication of the
concrete uniformity from batch to batch. Repeated batches of the same mix, brought to the same
slump, will have the same water content and water cement ratio, weights of aggregate, cement
and admixtures are uniform and aggregate grading is within acceptable limits.
Reliability

1. Slump test should not be carried out if the aggregates used is 40 mm.
2. Slump test won’t suit for the concrete mixture that is very dry concrete because it doesn’t
show the differences in heights.
3. Parallax error might be done by the person in charge during taking the measurement of
the components.
4. Concrete might not be thumped perfectly as the force applied each time released the
rod was not same.
Modification
1. We have to make sure that the aggregates used were below than 40 mm.
2. We should performed a relevant calculations so that slump test can be carried out for
the concrete.
3. The person in charge must place the eyes perpendicular to the scale to get the accurate
result.
4. We have to make sure that the rod must be released at approximately at the same
height to obtain same forces for every thumping process.
For this experiment, a slump test is conducted to check the workability of our fresh concrete and
how it flows. We filled the fresh concrete in the truncated conical mould and each layer being
compacted 25 times to reduce the segregation, now we removed the truncated conical mold and
we observed that the difference between height of slump concrete and the mold is 10mm, this
is due to the exist of water in the fresh concrete.
As the water-cement ratio is high the workability is also high, but the strength of concrete will be
reduced, the target strength of our concrete is 55 MPa so to get that strength we need a low

water-cement ratio which means a low workability for our fresh concrete. Thus, it is categorized
as a true slump.
The methodology of slump test is basic and simple than some other workability tests, slump test
can be performed at the development site and in the research facility.
The slump test is limited to concretes with the maximum size of aggregate less than 38 mm, also
the test is suitable only for concretes of medium or high workabilities (i.e having slump values of
25mm to 125 mm). For very stiff mixes having zero slumps, the slump test does not show any
difference in concretes of different workabilities.
Reliability
1. If the aggregate size is more than 38mm we can’t use the slump test.
2. With a very low water-cement ratio, slump test can’t be conducted well.
3. Parallax error occured while taking the reading of the difference height between the
slump concrete and the mold.
4. Each layer got different height when the compacting force were applied
Modifications
1 Make sure the size of the aggregate is lower than 38mm by the help of sieve analysis.
2 Make sure the fresh concrete is workable.
3 Make sure your eye is perpendicular to the reading scale.
4 Make sure the height interval for each layer is equal.
The slump test result is a measure of the behavior of a compacted inverted cone of concrete
under the action of gravity. It measures the consistency or the wetness of concrete. Generally
concrete slump value is used to find the workability, which indicates water-cement ratio, but
there are numerous factors including properties of materials, mixing methods, dosage,
admixtures etc. also affect the concrete slump value.

In this test, we can see that the results slump, which is indicate by the difference of height of the
conical mold with the height concrete. The difference is 10mm and type of slump we got was
true slump. As the slump is quite low, we can say that the workability for the concrete is low. This
is because the strength of our concrete mix is high, thus the water cement ratio is quite low.
In the industry, slump test is used to ensure uniformity for different batches of similar concrete
under field conditions. This test is very useful on site as a check variation in the materials being
fed into the mixer. An increase in slump may mean, for instance, that the moisture content of
aggregate has unexpectedly increases. This test is used to check the uniform quality of concrete
during construction.
Reliability
1. The concrete was not thumped perfectly using rod as different force was given while
thumping that may cause some variation.
2. Concrete might stick to the conical mould.
3. Parallax error might occur while taking the reading of height difference.
Modification
1. Release the thumping rod from about the same height and let it fall under influence of
gravity for uniform force.
2. Spread grease around inner part of mould to prevent concrete from sticking to the mould.
3. Make sure eyes are directly perpendicular to the ruler while taking the measurement to
prevent parallax error
CONCLUSION
As a conclusion, we can say that the objective to measure the workability of a sample from a
batch of fresh concrete of a given is achieved. In this experiment, we used slump test to measure
the workability. This test usually used in the site to determine the consistency of fresh concrete
from different batches. The results from this experiment showed that the workability for the
fresh concrete by our group is low as the slump is only 10mm.

COMPACTING FACTOR TEST- TEST FOR WORKABILITY
OBJECTIVE
To measure the workability of a sample from a batch of fresh concrete.
THEORY
A concrete mix should be workable enough so that it would be compacted well. Good compaction
is necessary in order to expel air voids in a fresh concrete mix. The presence of voids in concrete
greatly reduces its strength. Five percent of voids can results in a drop of strength of more than
10 percent.
The compacting factor is defined as the ratio of the weight or partially compacted concrete to
the weight of fully compacted concrete and is normally stated to the nearest second decimal
place.
Compacting factor = mass of partially compacted concrete
mass of fully compacted concrete
APPARATUS
The compacting factor test consist of two conical hoppers and a cylindrical container mounted
vertically above one another, a hand scoop, a steel trowel and a 16mm diameter and 600mm
long tamping rod.
PROCEDURE
1. The apparatus have been cleaned from any superfluous moisture.
2. The empty cylinder was weighed and the mass have been recorded in gram.
3. Fasten the hopper trap door with the catches. The cylinder was fixed on the base of the
apparatus. The cylinder top have been covered with two steel trowels.
4. The top hopper have been gently filled with concrete sample by using a hand scoop until
full. Level off or tamp or compact was not allowed.

5. The trap door of the top hopper was opened to allow the concrete to fall into the second
hopper. We have confirmed that no concrete sticks in the top hopper.
6. The steel trowel was removed from the top cylinder and trap door of the lower hopper
have been released to allow the concrete to fall into the cylinder.
7. The top of the cylinder have been leveled and spillage was removed from outside the
cylinder.
8. The cylinder was weighed with the partially compacted concrete. The mass have been
recorded in gram.
9. The concrete have been taken from the cylinder. The cylinder was refilled with the same
concrete in layer approximately 50mm deep.
10. Each layer was compacted by using a tamping rod for 35 strokes.
11. The top was leveled and the spillage was cleaned. Then the mould was weighed with fully
compacted concrete. Note the mass in gram.
PRECAUTIONS
a. Test should be carried out on a level surface or ground.
b. The hopper and cylinder must be thoroughly clean and dry.
c. If concrete sticks within the hoppers, push the concrete gently by using a tamping r
d. od
e. The outside of the cylinder must be wiped clean before weighing.
f. The test can be carried out within a period of 2hours from addition of water to the mix.

FIGURE 1: Compacting Factor Testing Apparatus
RESULT
Weight of empty cylinder = 6.4 kg
Weight of partially compacted concrete = 15.42 - 6.4 = 9.02 kg
Weight of fully compacted concrete = 17.54 – 6.4 = 11.14 kg
𝐶𝑜𝑚𝑝𝑎𝑐𝑡𝑖𝑛𝑔 𝑓𝑎𝑐𝑡𝑜𝑟 =
𝑚𝑎𝑠𝑠 𝑜𝑓 𝑝𝑎𝑟𝑡𝑖𝑎𝑙𝑙𝑦 𝑐𝑜𝑚𝑝𝑎𝑐𝑡𝑒𝑑 𝑐𝑜𝑛𝑐𝑟𝑒𝑡𝑒
𝑚𝑎𝑠𝑠 𝑜𝑓 𝑓𝑢𝑙𝑙𝑦 𝑐𝑜𝑚𝑝𝑎𝑐𝑡𝑒𝑑 𝑐𝑜𝑛𝑐𝑟𝑒𝑡𝑒
𝐶𝑜𝑚𝑝𝑎𝑐𝑡𝑖𝑛𝑔 𝑓𝑎𝑐𝑡𝑜𝑟 =
9.02
11.14
= 0.810

DISCUSSION
This test works on the principle of determining the degree of compaction achieved by a standard
amount of work done by allowing the concrete to fall through a standard height. The degree of
compaction, called the compacting factor is measured by the density ratio which is the ratio of
the density actually achieved in the test to density of same concrete fully compacted.
For the experiment,we are doing the test for fully compacted concrete and partially compacted
concrete.The result of compacting factor for is 0.181 which is can be categorized as low
workability.This is mainly due to the low content of water cement ratio.As we need to achieve
55 Mpa strength,low water cement ratio is needed to gain that strength.
From the experiment,we can observe that the weight of the partially compacted concrete is
lower than fully compacted concrete.This due to more spaces or void and air bubbles inside which
cause the density of the concrete to become low.
Reliability
1. Some other impurities might be found stick or left on the apparatus.
2. Zero button on the weighing scale was not calibrated to zero.
3. The concrete was not thumped perfectly to make the concrete compact.
Modification
1. The apparatus should be clean before the experiment conducted.
2. The person in charge for the thumping process should know the correct way for the
process.
3. We have to make sure that the scale must be zero before weighing the concrete and
cylinder.

(ASHIKIN MASTURA 23859)
This experiment shows the workability by using compacting factor test. compacting factor test is
the ratio of the weight of the concrete compacted in the compaction factor apparatus to the
weight of the fully loaded compacted concrete.
During lab session, the concrete was filled but not compacted. the concrete was allowed to drop
into lower hopper. Next, the door below was opened. The cement is now dropped to the bottom
cylinder. The excess concrete was struck off the top layer. Then the mass of the concrete is
recorded.
From the results obtain, we used the equation given to determine the compacting factor and it
was 0.81. The recorded value is considered to have low workability. This may due to the water-
cement ratio that was not enough mixed to the concrete mix to achieve optimum value to pass
compacting factor. Hence, the lower the water, the lower the workability.
We were able to find out the workability by calculating the compaction factor of our fresh
concrete in compacting factor test. Compacting factor can be defined as the ratio of concrete
that fall in a cylinder with the help of gravity to the weight of fully compacted concrete in the
same cylinder.
The compacting factor for our fresh concrete is 0.81 which is categorized under low
workability. This is due to the low water-cement ratio of the fresh concrete. For example, if the
fresh concrete has a higher water-cement ratio, more fresh concrete will be flowing into the
cylinder resulting an increasing of weight and causing a higher ratio of compacting ratio. Besides,
a higher water-cement ratio of fresh concrete can flow easily with the help of gravity as they
behave more fluidity and mobility compared to a lower water-cement ratio fresh concrete.
Furthermore, more force was needed to compact our fresh concrete as it behave in low
workability. The lower the water-cement ratio, the more difficult to compact the fresh concrete.

However, higher water-cement ratio of fresh concrete has a higher workability but segregation
or bleeding may occur in the concrete. Thus, we can predict that our fresh concrete has a low risk
of segregation and bleeding.
From the result obtained, we can observe that the mass of fully compacted fresh concrete
has a higher weight compared to mass of partially compacted fresh concrete. This is because that
fully compacted fresh concrete has lesser free space or voids in it and the distance between each
other is also lesser compared to the partially compacted fresh concrete.
Compacting factor test is better than slump test due to its accuracy and sensitivity. This is
because concrete mixes of very low workability can be tested out through compacting factor test
whereas in slump test it is difficult and less convenient resulting a less accuracy of results.
Reliability
1. The apparatus of this experiment were slightly inclined and causing the weight of the
fresh concrete not perpendicular to the ground.
2. There was some concrete left on the surface of cylinder when weighing the weight of
fresh concrete together with the cylinder container.
3. The ‘Zero’ button on the weighing machine was not pressed and causing a zero error.
Modification
1. Make sure the apparatus were not inclined by placing them on an even surface.
2. Wipe the cylinder container and make sure no concrete left on it before weighing the
fresh concrete together with the cylinder container.
3. Press the ‘Zero’ button to calibrate the weighing machine to zero before placing the fresh
concrete together with the cylinder container on it to avoid zero error.
( By: Muhammad Haziq Hazim Bin Abd Halim 23901)
Compacting factor test can indicate the workability in the concrete which describe how easily can
the concrete be vibrated and compacted. This test is also good indicator of the mobility and
flowability of concrete as it show how easily the concrete will pass the trap door after it was

opened. From the calculation above, the compacting factor is 0.81. For normal range of concrete
the compaction factor lies between (0.8 – 0.92) so, the value obtained tells us that the workability
of our concrete is low.
There are some factors that can affect the compacting factor. The compaction factor can
be affected by changing the water/cement ratio. Increasing the water cement ratio will increase
the compacting factor. The higher the water cement ratio, the greater the initial spacing between
the cement grains that will result higher presence of residual voids. A lower water cement ratio
means less water, or more cement and lower workability. But if we placed too much water would
have resulted in decreasing compacting factor as increasing the water content will result in
lowered compacting factors. Lower compacting factors will have low workability that will make
the concrete becomes difficult to compact and reduces in strength.
Aggregates also can affect the compacting factor therefore the workability of concrete.
Size, shape and grading of aggregates play an important on the workability of concrete. The
concrete having large sized aggregates is more workable because less amount of water required
for lubricating the surface to reduce the friction while rounded aggregates consider to have less
surface area and less voids in comparison to angular aggregates and also provide better
possibility to overcome the frictional resistance. While well graded aggregates, the amount of
voids will be less and hence higher the workability.
Reliability
1. Some other impurities might be found stick or left on the apparatus.
2. Zero button on the weighing scale was not calibrated to zero.
3. The concrete was not thumped perfectly to make the concrete compact.
Modification
1. The apparatus should be clean before the experiment conducted.
2. The person in charge for the thumpling process should know the correct way for the
process.
3. We have to make sure that the scale must be zero before weighing the concrete and
cylinder.

By calculating the compaction factor of our fresh concrete in the compacting factor test, we
were able to observe the workability. Compacting factor is the ratio of the weight of concrete
which fills a container of standard size and shape (when allowed to fall into it under standard
conditions of test) to the weight of fully compacted concrete which fills the same container.
We obtained a 0.810 value for our compacting factor, which is stated to be a low workability.
low water-cement ratio leads to a low workability, meanwhile a higher water-cement ratio leads
to a high workability, means that it can flow easily and behave like fluidity, with the help of the
gravity.
Since our fresh concrete has a low workability the chance for segregation or bleeding to occur is
very low and more force is needed while compacting, excess increase in the water-cement ratio
to get a better workability might lead to segregation and bleeding.
In our result, we got a different weight of concrete, one when it was partially compacted, and
the other was when it is fully compacted.
The density for the fully compacted concrete is higher than the partially compacted concrete due
to some open space or air in between in the partially compacted concrete. Thus, the weight for
partially compacted concrete is lower than fully compacted concrete.
Compacting factor test is suitable for testing workability in laboratories and for low workability
concretes.
Also, it is suitable to detect the variation in workability over a wide range and the results are
more precise and sensitive.
Reliability
1. The weighing device was not set exactly to zero while weighing.
2. While compacting, the force was not always the same.
Modification

1. Before weighing, make sure the weighing device is set to zero.
2. To ensure the force are almost equal, leave the rod to fall by the gravity force at the same
height.
(Nur Ain Syafiqah binti Abdul halim, 25598)
Compacting factor test is a test to determine the workability of concrete. The workability of
concrete can be obtained by finding the ratio of mass of partially compacted concrete to mass of
fully compacted concrete. This ratio is called compacting ratio. This factor also related to the
workability of the concrete. The higher the compacting factor, the higher the workability is.
From the results we can have calculated that the compacting factor for the concrete was
0.81. It is considered as low workability. Furthermore, the concrete appeared to be dry and it was
quite difficult to pass through the trapdoor when it was opened. Therefore, we can say that the
workability of the concrete mix was low. This may due to low water-cement ratio of the concrete
as the strength expected for the concrete was quite high, which was at 55 MPa. Therefore, less
water means, less workability.
From the results, we can also see the difference in weight of concrete when it was partially
and fully compacted. The weight for partially compacted is lower than fully compacted concrete.
This is because the density for fully compacted concrete is higher compared to partially
compacted concrete. This is due to existence of more voids and free space in partially compacted
concrete, thus making the density lower.
This test is useful as it can measure workability, better compared to slump test especially
for concrete with low workability. However, as the apparatus is heavy and complicated, this test
is not commonly used to work at the construction site.
Reliability
1. Zero error might occur when using the weighing machine.
2. Too much force might be given when tamping the layers of concrete.

Modification
1. Press the ‘Zero’ button to calibrate the weighing machine to zero before placing the fresh
concrete together with the cylinder container on it to avoid zero error.
2. Release the tamping rod at about the same height every time, and let it fall due to gravity
to ensure the force is about constant.
CONCLUSION
In conclusion, there are some factors that can affect the compacting factors and thus the
workability of concrete. The workability of concrete is considered low based on the compacting
factor which is 0.81 The most affected factors on the workability of concrete is the water cement
ratio. We can say that too little water cement ratio reduces the strength of concrete but if the
water cement ratio is too high, it can result in porous concrete. So, an exact amount need to be
used to obtain best result, depending on the function of the concrete. Hence, we can say that
the objective to measure the workability of a sample from a batch of fresh concrete, is achieved.

VEE BEE CONSISTOMETER TEST
OBJECTIVE
The method of the test covers the procedures for measuring indirectly the workability of concrete
and also for determining in consistency of very dry mixes.
APPARATUS
Vibrating table, a metal pot, a sheet metal cone and standard iron rod.
PROCEDURE
1. The slump cone was placed inside the sheet metal cylindrical pot of the consistometer.
2. The attached glass disc was turned to the swivel arm and placed on the top of the
concrete in the pot.
3. The electric vibrator have been switched on and simultaneously the stopwatch was
started.
4. The time of vibrator was taken till conical shape disappear and the concrete assumes
cylindrical shape.
FIGURE 1: VEE-BEE CONSISTOMETER

RESULT
The time required for complete remolding in seconds = 13.11 s
The consistency of the concrete is recorded in seconds. The time recorded was 13.11 s which
means the workability of our concrete is considered very stiff.
DISCUSSION
(Afnan Munir bin Mohd Khairi 23779)
The main objective of Vee-Bee test is to determine the workability of the freshly mixed concrete.
The Vee-Bee test gives an indication about the mobility and the compactibility aspect of the
freshly mixed concrete.Vee-bee test carries out the relative effort measurement to change the
mass of the concrete from a definite shape to the other. That is, as per the test, from the conical
shape to the cylindrical shape by undergoing vibration process.In the cases of concrete mixes
that have slump value greater than 125mm, the phenomenon of remoulding is found to be very
quick and the time cannot be measured. This means that the Vee bee test is not suitable for
measuring the mobility of concrete of higher workability. This higher workability comes in the
range of slump value greater than 75mm.
Based on the result, the Vee-Bee seconds for the freshly mixed concrete was 13.11 s, which the
workability is considered as very stiff. Therefore, we can say that the workability for the concrete
is low. This is because the water-cement ratio for the concrete was low as the strength expected
was 55 MPa, which is considered as high.
The workability can be affected due to many factors.Low water cement ratio will contribute to
low workability.Mixture that contain more porous aggregates will have low workability as it
require more water compared to others.
Reliability
1. Some impurities trapped in the apparatus will cause inaccuracy.
2. The concrete hardened before starting the experiment.
3. The time takers not react properly when taking the time.

Modifications
1. Make sure that the apparatus is cleaned properly before the experiment.
2. Continuously mixing the the cement to prevent the concrete hardened quickly.
3. Assign 2 people to take the time and take the average for a better data.
The Vee-Bee test is to determine the workability of the freshly mixed concrete. The Vee-Bee test
gives an indication about the mobility and the compactibility aspect of the freshly mixed
concrete. It carries out the relative effort measurement to change the mass of the concrete from
a definite shape to the other. That is, as per the test, from the conical shape to the cylindrical
shape by undergoing vibration process. The measurement of the effort is done by time
measurement in seconds. The amount of work measured in seconds is called as the remolding
effort. The time required for the complete remolding is a measure of the workability and is
expressed in the Vee-Bee seconds. The method can be also applied for dry concrete. For concrete
that have slump value more than 50mm, the remolding activity will be so fast that the
measurement of time is not possible.
From this experiment, we were able to learn that Vee Bee Consistometer is also one of
the test for the workability of fresh concrete. Each layers of fresh concrete in the slump cone was
compacted for 25 times in order to maintain the cohesive and prevent segregation of fresh
concrete. From the result obtained, the time taken for the fresh concrete to remold completely
is 13.11 seconds.
Workability of fresh concrete can be defined as the ease of working on the concrete. It
has a close relationship with the water-cement ratio as the lower water-cement ratio will cause
a lower workability of fresh concrete. The time taken for the fresh concrete to remold completely

is inversely proportional to the workability of fresh concrete(𝑡𝑖𝑚𝑒 𝛼
1
𝑤𝑜𝑟𝑘𝑎𝑏𝑖𝑙𝑖𝑡𝑦
). In other words,
the shorter the time taken for the fresh concrete to remold, the higher the workability of fresh
concrete.
Furthermore, we can predict that our fresh concrete has a very low risk of segregation.
This can be proved by the slow time taken for the fresh concrete to remold completely and also
the good grading of particles used in concrete. Good grading of particles can be defined as there
is less space in concrete for water to pass through. This grading is caused by the rounded particles
in our fresh concrete. The rounded particles are only able to create a very tiny space between
each other compared to angular shape particles. Thus, the tendency to trap the water is higher
for the rounded particles and as a result, causing the concrete to be more cohesive and behave
a stronger compressive strength.
Thus, after the Vee Bee Consistometer test, we can conclude that our fresh concrete have
a low workability and therefore has a high compressive strength. Since the expected compressive
strength for our group is 55 MPa, therefore we can say that our concrete mixing is in a right path.
Reliability
1. All the apparatus used in this experiment were not clean enough or contaminated with
impurities before the experiment start.
2. Lack of hand-mixing on the fresh concrete resulting the fresh concrete from setting too
fast in the apparatus or in the wheelbarrow.
3. The reaction time of the time keeper was not accurate enough to record the time for the
fresh concrete to remold completely.
Modification
1. Make sure that the apparatus are washed with clean water then let it dry for a while and
make sure no suspended solid left in the apparatus.
2. Make sure that the hand-mixing on the fresh concrete was continuous throughout the
whole experiment to prevent it from setting too fast.

3. Appoint another 2 students as timekeeper to record the time and take an average value
of it to minimize the inaccuracy of result obtained.
(By: Muhammad Haziq Hazim Bin Abd Halim 23901)
The Vee-Bee Consistometer was used to measures the remoulding ability of concrete under
vibration. Vee-Bee test was just like the slump test which only measures the consistency but
more to the mixtures of concrete with low consistency. The time was taken according to the
shape of a concrete mix that needed to transfer from a cone to a cylinder and it is called vebe
time. The vebe time recorded was used to determine the workability of the concrete.
The more vebe time needed the less workable the mixture is. From the time recorded
which is 13.11 s, we can considered that our concrete is very stiff which have low workability in
order to achieve the targeted strength, 55 MPA.
The workability of concrete can be affected by many factors. It is found that our concrete
mixture has low workability from the test conducted. One of the factors that proved a concrete
has low workability because of low the water cement ratio. Mixture that contain more porous
aggregates will have low workability because it require more water compared to others. Shape
of the aggregates also affected the workability of concrete. The rounded aggregates will be more
workable as it have less surface area and less voids compared to angular one. Some other factor
that will affect the workability is the grading of aggregates. A well graded is the one which has
least amount of voids in a given volume and higher the workability.
Reliability
1. Due to the need to ensure that all vibration is kept within the test device, the size of the
test device makes the Vebe consistometer generally unsuitable for field use.
2. The test device only works for low slump concretes.

3. No analytical treatment of the test method has been developed. Such treatment would
be complex because the shear rate declines during the duration of the test as the concrete
specimen changes shape.
Modification
1. Make sure the person in charge for taking the know when to take the time for Vebe test.
2. The test should be done in a period of time to ensure for an accurate result
Vee Bee consistometer, is one of the workability tests for our fresh concrete, in slump cone each
layer were compacted 25 times to avoid segregation from taking place, from our results we can
see that the time required for completion of remolding is 13.11sec.
In very simple words we can say that workability of concrete means the ability to work with
concrete. A concrete is said to be workable if. It can be handled without segregation. It can be
placed without loss of homogeneity. It can be compacted with specified effort.
Workability is directly proportional with the water-cement ratio, as the water-cement ratio
increase the workability will increase. The time is inversely proportion to the workability , the
lower the time taken for remold, the higher the workability.
Since in our experiment it didn’t take much time, only 13.11 sec so we can observe that there is
low risk of segregation, thus the concrete will be more cohesive and stronger.
So, we can say that the results of this test are of value when studying the mobility of the masses
of concrete made with varying amounts of water, cement and with various types of grading of
aggregate.

Reliability
1. The impurities trapped in the apparatus from previous experiments might cause incorrect
results for our experiment.
2. The concrete is almost hardened before starting the experiment.
Modification
1. Make sure to clean apparatus from impurities before conducting the experiment.
2. Make sure to mix the fresh concrete frequently so it doesn’t harden faster.
Vee-Bee test is one of the test to measure the workability of fresh concrete mix. It gives an
indication about the mobility and compatibility of the freshly mixed concrete. The measurement
of the effort is done by time measurement in seconds. The amount of work measured in seconds
is called as the remolding effort. The time required for the complete remoulding is a measure of
the workability and is expressed in the Vee-Bee seconds.
From this experiment, the Vee-Bee seconds for the freshly mixed concrete was 13.11 s,
which the workability is considered as very stiff. Therefore, we can say that the workability for
the concrete is low. This is because the water-cement ratio for the concrete was low as the
strength expected was 55 MPa, which is considered as high.
The more Vee-Bee seconds needed the less workable the mix is. We can say that the time
taken for the fresh concrete to remold completely is inversely proportional to the workability of
fresh concrete(𝑡𝑖𝑚𝑒 𝛼
1
𝑤𝑜𝑟𝑘𝑎𝑏𝑖𝑙𝑖𝑡𝑦
). Therefore, this method is very useful for stiff mixes and not
suitable for measuring the mobility of concrete of higher workability. This is because, the higher
the workability, the shorter the time is and it can go to the point where it is difficult to measure
the time if the workability of concrete is very high.

This test is not usually used at the site due to its quite complicated set up. In addition,
difficulties in establishing the endpoint of the test is a source of error. Even so, this test is better
compared to compacted factor test as it will not go through problem of sticking of concrete in
the hoppers of the compacting factor apparatus.
Reliability
1. Presence of impurities and dried concrete in the apparatus might cause inaccuracy .
2. Concrete is hardened before doing the experiment.
3. Human error when taking the time as there are delay in reaction might cause inaccuracy
in the experiment.
Modification
1. Clean the apparatus before using it.
2. Continuously hand-mixed the concrete to make sure it does not hardened before the test.
3. Carry out the test few times and take average reading, or assign another 2 people to take
the time while doing the experiment once, and take the average.
CONCLUSION
From the vebe test conducted, we can say that the concrete mixture has low workability. It is
because that the time taken for completing remoulding is higher and the concrete is very stiff.
Therefore, the objective to measure indirectly the workability of concrete and also for
determining in consistency of very dry mixes, is achieved.

COMPRESSIVE STRENGTH TEST CUBES – TEST FOR STRENGTH
OBJECTIVE
To determine the compressive strength (crushing strength) of concrete according to BS 1881:
Part 116:1983.
THEORY
One of the most important properties of concrete is its strength in compression. The strength in
compression has a definite relationship with all other properties of concrete. The other
properties are improved with the improvement in compressive strength.
The compressive strength is taken as the maximum compressive load it can be carry per
unit area. Compressive strength tests for concrete with maximum size of aggregate up to 40mm
are usually conducted on 150mm cubes.
APPARATUS
Compression Testing Machine (it complies with the requirement of BS 1610).
PROCEDURE
1. The specimen was removed from curing tank and surface water was wiped and gritted off
the specimen.
2. Each specimens were weighted to the nearest kg.
3. The top of the testing machine were cleaned and lowered the top.The cube was carefully
centered on the lower platen and ensured that the load will be applied to two opposite
cast faces of the cube.
4. The load was increased and applied continuously without shock at a nominal rate within
the range 0.2N/mm2 to 0.4 N/mm2 until no greater load can be sustained.The maximum
load applied to the cube was recorded.
5. The type of failure and appearance of the rocks was recorded.

6. The compressive strength of each cube was calculated by dividing the maximum load by
the cross sectional area. The result was expressed to the nearest 0.5 N/mm.2.
Calculation Procedure
Volume of the cube
=(0.1 x 0.1 x 0.1)
= 0.001𝑚3
Density of concrete(kg/𝑚3
) =
𝑤𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑡ℎ𝑒 𝑐𝑜𝑛𝑐𝑟𝑒𝑡𝑒
𝑣𝑜𝑙𝑢𝑚𝑒 𝑜𝑓 𝑡ℎ𝑒 𝑐𝑜𝑛𝑐𝑟𝑒𝑡𝑒
Cross-sectional area
=(100 x 100)𝑚𝑚2
=10000 𝑚𝑚2
Compressive strength(N/𝑚𝑚2
)
=
𝐹𝑎𝑖𝑙 𝑙𝑜𝑎𝑑
𝑐𝑟𝑜𝑠𝑠−𝑠𝑒𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝑎𝑟𝑒𝑎

RESULT
Figure 1: The sample after compressed Figure 2: Example of non-explosive failure of cubes
Figure 3: An example of explosive failure of test cube Figure 4: Compression machine

Figure 5:The test cubes were exposed under Figure 6: More example of test cube after
the sun compression
Figure 7: Compression machine showing the result Figure 8: Result of the test cubes after 28
days

COMPRESSIVE STRENGTH RESULT
Marking Date
Cast
Age
Days
Dimension
(mm)
Weight
(kg)
Weight/Vol
kg/m3
Fail
load
(KN)
Strength
N/mm2
crushing
6 4/10/1
7
7
days
100 2.28 2280 436.4 43.64
3 4/10/1
7
7
days
100 2.19 2190 469.8 46.98
4 4/10/1
7
14
days
100 2.36 2190 553.5 55.35
5 4/10/1
7
14
days
100 2.36 2360 607.2 60.72
1 4/10/1
7
28
days
100 2.30 2300 675.9 67.59
2 4/10/1
7
28
days
100 2.40 2400 708.0 70.80
Table 1: The compressive strength result

DISCUSSION
(BY AFNAN MUNIR BIN MOHD KHAIRI 23779)
In this experiment, we are looking for the compressive strength for the cubes after 7 days, 14
days and 28 days. Compressive strength is the applied pressure at which a given concrete sample
fails. Compression is the vital issue in structural building. The strength of concrete is controlled
by the proportioning of cement, coarse and fine aggregates, water, and various admixture. The
ratio of the water to cement is the chief factor for determining concrete strength. The lower the
water-cement ratio, the higher is the compressive strength. The strength in compression has a
definite relationship with all other properties of concrete. The other properties are improved
with the improvement in compressive strength. Concrete gain strength with time after casting.
The rate of gain of concrete is higher in the first 28 days of casting and slow down afterward.
Based on result in the Table 1, after 7 days we have achieved strength of 43.64 MPa and 46.98
MPa . For 14 days, we achieved strength of 55.35 MPa and 60.72 MPa and for 28 days, we
achieved 67.59 MPa and 70.80 MPa. Although we have exceed the target strength of 55 MPa, we
still achieved our target mean strength of 70.68 MPa. Thus, we can say that we achieved our
target strength that has been tasked for our group.
RELIABILITY
1. The water in the cube that is not thoroughly dry can result into false reading of the weight
of the cube.
2. The cube is not place at the center in the compressive machine will make the pressure is
not evenly distributed.
3. The cube is not lock properly in the machine can cause the cube to move during the
compression of the cube.
MODIFICATION
1. Make sure that the water in the cube is thoroughly dry by placing the cube under the sun
for about 15-20 minutes.
2. Place the cube properly in the center of the compressive machine.

3. Lock the cube tightly to prevent the cube from moving during the test conducted.
Previously, we had done our concrete mix design and from there the fresh concrete mix
moulds were left for one full day to dry and for it to settle before doing the next procedure, curing
in the curing tank to make sure that concrete’s pores are tightens.
From the experiment carried out, we were required to test out the cubes’ compressive
strength at 3 different days. The significant of testing this compressive strength is to determine
overall strength of a structure such as flexural resistance and abrasion directly depends upon the
compressive strength of concrete. We measured the cubes on day 7, 14 and 28 because concrete
is a macro content with sand, cement and coarse aggregate as its mix ratio and gains its 100 %
strength over time at the hardened state. This means that, as time passes, the strength gain
gradually increases and reaches 100 % strength gain at day 28.
On day 7, the concrete strength should obtain at least 70 % of the specified strength.
Based on the result obtained on day 7, the strength of the two cubes (cube 6 and cube 3) were
43.64 MPa and 46.98 MPa respectively. By using equation, we managed to calculate that the
cubes obtained (79.35 % and 85.42 % minimum strength. Thus, the compressive strength of
concrete cubes on day 7 is successful and passed the specified strength.
On day 14, the concrete strength of cubes 4 and 5 has reached 55.35 MPa and 60.72 MPa.
Although the values are higher than the specified strength (55 MPa) but we assume that it is
acceptable as it still falls in the range of our target mean strength.
On the last day, day 28, the strength of the concrete reached 67.59 MPa for cube 1 and
70.80 MPa for cube 2. The values falls in between the range of our target mean strength. All in
all, our concrete mix design was calculated well and was executed successfully as it reached its
100 % strength gain of 55 MPa.

The concrete made by us was gone through many process such as batching, mixing,
compacting and curing of materials. The fresh concrete moulds were left for 24 hours to allow
setting before placing in the curing tank for curing.
Before the starting the compressive strength, concrete cubes were stayed in the curing
tank for curing. From the result obtained, we can obvious that they compressive strength is
increasing with time (day). The main purpose of curing is to maintain a constant excess of
moisture or a sufficient of water supply for concrete to complete hydration. The objective of
curing is to keep concrete saturated or nearly saturated so that the originally water-filled space
in the concrete paste has been filled to the desired extent by the products of hydration.
At 7 days, the concrete strength should be obtained 70% of the grade of
concrete(minimum strength) which is 55 MPa. By dividing the strength of concrete cube 6 (43.64
𝑁
𝑚𝑚2
) and cube 3 (46.98
𝑁
𝑚𝑚2
) by 55 MPa and multiply with 100%, we found that both of the
concrete cubes obtained 79.35% and 85.42% of minimum strength for cube 6 and cube 3.
Besides, the units are actually the same for
𝑁
𝑚𝑚2
and MPa as the unit of Pascal, Pa:
Compressive strength=
𝑁
𝑚𝑚2x
𝑁
10−6𝑚2
=
𝑀𝑁
𝑚2
= MPa
Thus, we can say that the compressive strength of our concrete cubes at 7 days had reached or
slightly more than 70% successfully.
At 14 days, the concrete strength for cube 4 and cube 5 reached 55.35 Mpa and 60.72
MPa. At 28 days, we can obvious that our concrete cube 1, and cube 2 were achieved 2300 kg/m3
and 2400 kg/m3 respectively. The density of concrete is a measurement of concrete’s solidity.
These density shown that our concrete achieved the normal density of concrete which is in the
range of 2200 to 2600 kg/m3.
At 28 days, our concrete achieved 67.59 MPa for cube 1 and 70.80 MPa for cube 2. This
compressive strength for these 2 cubes were range within our grade of concrete(minimum
strength), 55 MPa and the target mean strength(maximum strength), 70.68 MPa which shown in

appendix 1. There was a minor error where the concrete cube 2 obtained a higher strength than
the target mean strength. However, this small minor increment will not affect our compressive
strength of concrete made compared to the expected compressive strength as the increment
was only 0.12 MPa. This minor error may due to the uneven surface of the both side such as voids
of concrete that are going to be compressed in the Compression Testing Machine.
RELIABILITY
1. The concrete cubes were not dried enough and the top and lower platens of the testing
machine were not cleaned before starting the compression test.
2. The cubes were not place at the center of the Compression Testing Machine and causing
a non-uniform force distribution on the cubes which affecting the value of compressive
strength.
3. The cubes were not hold tightly at the center and this may cause the movement of
cubes when the compression start
MODIFICATION
1. Make sure all the concretes cube were dried by exposing them under the sunlight before
starting the compression test.
2. Place the cubes at the center of the Compression Testing Machine so that the force
applied on the cubes can be uniformly distributed so that a higher accuracy reading of
compressive strength can be obtained.
3. Make sure the cubes were hold tightly in the center to prevent them from moving.
The compressive strength is measured by using the cubes specimen in a compression machine.
The compressive strength is calculated from the failure load divided by the cross-sectional area
resisting the load and it is reported in mega Pascals (MPa) units. The compressive strength of
concrete is the most common performances measure used by the engineer in designing buildings
and other structures. Usually compressive strength test result are used to determine that the
concrete mixture whether it meets the requirements of the specified strength as for our case is
55 MPa.

For this experiment, we carried out three compressive strength tests which is on 7th, 14th and 28th
day by using two cubes for each test. All the six cubes need to be cure in container of water at a
specified temperature which is 27 degree Celsius after the demoulding process. The concrete
need curing as the chemical reactions need to proceed continuously in order for concrete to
develop strength. Curing is important for maintaining of a proper environment for the hydration
reactions to proceed and it is carried out at the porous section where there is less amount of
water.
On the 7th days, we should achieve at least 70% of the specified strength. Based on the
result obtained on that day, the strength of the two cubes was 43.64 MPa and 46.98 MPa and it
was slightly higher than the specified strength. For the test on 14th day, the strength of concrete
was 55.35 MPa and 60.72 MPa. Even though the values obtained is higher than specified strength
which is 55 MPa but we can considered that is still relevant because it is still in the range of our
target mean strength. On the 28th day, the strength of the concrete was 67.59 MPa and 70.80
MPa and we can say that the target mean strength was successfully achieved even there is a little
bit differences between the final value and calculated value which is 0.12 MPa increment.
Based on the final result, our concrete mix design calculation can be used to achieve to
specified strength which is 55 MPa. For a higher strength concrete, the water cement ratio will
be low to make the workability of the concrete also low. So the concrete mixture can resist a high
load on it. Strength of concrete is based on the proportioning of cement, aggregates, water and
admixtures.
Reliability
1. There was an excess water in the cubes after taking out from the water.
2. The cube was not place exactly at the center of the compressive machine so that
the pressure was not uniformly distributed.
3. There is a movement during the compression test as it was not locked properly
before.

4. There is some dirt stick at the sides of the cubes.
Modifications
1. The cubes must be placed under the sun for drying process for about 15-20 minutes
before the compression test.
2. Make sure that the cubes at the center before locked.
3. Try to push the cubes by our hand for ensuring it have been locked tightly.
4. Applying some oils on the inner surfaces of the concrete mould.
Our concrete has gone through different processes like, batching -> mixing -> transporting ->
placing -> compacting -> curing, the fresh concrete was left for 24 hours before placing it into the
curing tank for settling to take place.
The concrete stayed in the curing tank to maintain an excess amount of moisture of water supply
for the concrete to complete the hydration process, as we can see in our results the compressive
strength is increasing with the time taken while it is in the curing tank.
At 7 days, the concrete strength should be around 70% of our concrete grade which is 55 MPa.
We achieved 43.64Mpa and 46.98 MPa for cube 6 and 3 respectively, we found out that the
percentage obtained for these two cubes are 79.35% and 85.42% respectively. So, we can say
our concrete after 7 days reached around 70%.
At 14 days, we found that our concrete strength is 55.35MPa and 60.72 MPa for cube 4 and 5
respectively, and we also found out that our density of concrete falls between 2200 to 2600
kg/m3 which a normal density for any concrete.
At 28 days, we achieved around 67.59MPa and 70.80 for cube 1 and 2 respectively, hence they
fall within our strength range which is 55 MPa + the target mean strength = 70.68Mpa shown in
appendix 1.

It is important to conduct this test to track down our strength percentage for 7, 14 and 28 days.
Reliability
1. Water might still be trapped inside the cube after taking it out from the tank.
2. The cube was not exactly in the center of the compressive machine.
3. The cube might be moving while the test is conducted.
Modification
1. Make sure to dry the cube by exposing it to the sunlight outside.
2. Make sure the cubes are placed correctly in the center to get the pointed load at the
center.
3. Make sure to fit the cube as it doesn't have any chance of movement inside the test.
The best way of checking weather concrete can withstand certain compressive strength is by
carrying out compressive strength test on the cube. However, this test is destructive which
means, the concrete cube can no longer be used after the test as it was tested until it fails.
Compressive strength is defined as the resistance to failure under the action of compressive
force. It is calculated by dividing the failure load with the area of application of load. For concrete,
compressive strength is very important as it indicates the performance of material.
Usually, this test is carried out on the seventh and 28th day after the concrete was made.
For this experiment, we carried out compressive strength test on the 7th, 14th and 28th day after
the concrete was made. After demoulding of the formwork of the concrete, the concrete cubes
were cured in bath of water. This is for hydration process to continue, thus the strength of
concrete will develop over time, as long as hydration reaction still occur.
On the 7th day, the strength of the concrete was 43.64 MPa and 46.98 MPa. The expected
strength developed in 7 days is 70% of expected strength. The strength obtained was higher than
expected strength. On the 14th day, the strength of concrete was 55.35 MPa and 60.72 MPa.
These value is higher than our target 55 MPa strength, but since it is still in the range of our target

mean strength, we can say that the strength development is good. On the 28th day, the strength
obtained was 67.59 MPa and 70.80 MPa. Since our target mean strength is 70.68 MPa, we can
say that the strength of the concrete is well developed and achieved its target strength.
The strength of concrete is controlled by the proportioning of cement, coarse and fine
aggregates, water, and various admixtures. The ratio of the water to cement is the chief factor
for determining concrete strength. The lower the water-cement ratio, the higher is the
compressive strength. By this test we can decide whether Concreting has been done properly or
not.
RELIABILITY
1. Presence of water in concrete might cause inaccuracy while weighing it.
2. The value of compressive strength might not be accurate if the cube is not put at the
centre of the Compression Testing Machine.
3. The cube might move during the test if it is not lock tightly at the beginning of the test.
MODIFICATION
1. Make sure the cubes are dried by exposing it to the sun before starting test.
2. Ensure that the cube was put at the centre of the machine to make sure the force is
uniformly loaded .
3. At the beginning, lock the cube tightly before starting the test.
CONCLUSION
From the experiment conducted, we were able to achieve the objective of determining the
compressive strength of our concrete for 7 days, 14 days and 28 days. Based on the result, we
can say that our concrete has achieved the target strength of 55 MPa. This experiment is very
important for us civil engineers in order to know the strength of concrete so that we can avoid
any failure in our construction.

AGGREGATE TESTING
Date of laboratory: 24th September 2017
SIEVE ANALYSIS OF FINE AND COARSE AGGREGATES
OBJECTIVE
This test method covers the determinations of the particle size distribution of fine and coarse
aggregates by sieving. A weighed sample of dry aggregate is separated through a series of sieves
of progressively smaller openings for determination of particle size distribution.
APPARATUS
1. Scale (or balance) – 0.1g accuracy for fine sieve analysis
– 0.5g accuracy for coarse sieve analysis
2. Sieves
3. Mechanical Sieve Shaker
4. Drying oven (110 +/- 5C)
Figure 1 Electronic balance Figure 3 Fine Aggregate Sieves

Figure 2 Coarse Aggregate Sieves Figure 4 Mechanical Sieve Shaker
PROCEDURE
a. The sample was dried to constant weight at a temperature of 110 +/- 5C.
b. A suitable sieve size was selected to obtain the required information as specified. The
following sieves were applied with reference to ASTM C33 :
Coarse Aggregate (mm) Fine Aggregate (mm)
25.00 5.00
20.00 2.36
14.00 1.18
10.00 600 𝜇𝑚
5.00 300 𝜇𝑚
3.35 150 𝜇𝑚
2.36 163 𝜇𝑚
Pan Pan
Table 1 : Size of sieve stack for Coarse and Fine Aggregate

c. The sieves were nested in order of decreasing size of opening from the top to bottom.
The pan was placed below the bottom sieve. The lid was placed over the top sieve.
d. The sieves were agitated by hand or by mechanical apparatus for a sufficient period such
that not more than 1% by weight of the residue on any individual sieve will pass that sieve
during 1 minute of additional hand sieving. These criteria were accomplished after ten
minutes of original sieving.
e. The weight of material retained was determined on each sieve. The total retained weight
was closely match to the original weight of the sample.
RESULTS AND CALCULATIONS
RESULTS IN (APPENDIX 2)
a. Calculate the percentage passing and total percentage retained to the nearest 0.1 % of
the initial dry weight of the sample.
b. Calculate the fineness modulus as follow:
Fine Aggregate:
𝐹. 𝑀
=
{𝛴(𝐶𝑢𝑚𝑢𝑙𝑎𝑡𝑖𝑣𝑒 % 𝑅𝑒𝑡𝑎𝑖𝑛𝑒𝑑 𝑜𝑛 #5.00, 2.36, 1.18, 600 𝜇𝑚, 300 𝜇𝑚, 150 𝜇𝑚, 163 𝜇𝑚 𝑠𝑖𝑒𝑣𝑒𝑠)}
100
Coarse Aggregate:
𝐹. 𝑀 =
{𝛴(𝐶𝑢𝑚𝑢𝑙𝑎𝑡𝑖𝑣𝑒 % 𝑅𝑒𝑡𝑎𝑖𝑛𝑒𝑑 𝑜𝑛 #25, 20, 14, 10, 5, 3.35 2.36 𝑠𝑖𝑒𝑣𝑒𝑠)}
100
The mass loss was calculated to ensure such that the sieves were agitated by mechanical
apparatus for a sufficient period that is not more than 1% by weight of the residue.
𝑚𝑎𝑠𝑠 𝑙𝑜𝑠𝑠 𝑑𝑢𝑟𝑖𝑛𝑔 𝑠𝑖𝑒𝑣𝑒 𝑎𝑛𝑎𝑙𝑦𝑠𝑖𝑠 =
𝑤𝑡 − 𝑤1
𝑤𝑡
× 100

i. Fine Aggregate
=
500 𝑔 − 499 𝑔
500 𝑔
× 100
= 0.2 ≪ 1 % 𝑎𝑐𝑐𝑒𝑝𝑡𝑒𝑑
ii. Coarse Aggregate
=
2 000 𝑔 − 1 998 𝑔
2 000 𝑔
× 100
= 0.1 ≪ 1% 𝑎𝑐𝑐𝑒𝑝𝑡𝑒𝑑
To calculate the weight retained (g),
𝑐𝑜𝑙𝑢𝑚𝑛 4 = 𝑐𝑜𝑙𝑢𝑚𝑛 3 − 𝑐𝑜𝑙𝑢𝑚𝑛 2
To calculate the percentage retained (g),
𝑐𝑜𝑙𝑢𝑚𝑛 5 =
𝑖𝑛𝑑𝑖𝑣𝑖𝑑𝑢𝑎𝑙 𝑤𝑒𝑖𝑔ℎ𝑡 𝑐𝑜𝑙𝑢𝑚𝑛 4
𝑡𝑜𝑡𝑎𝑙 𝑤𝑒𝑖𝑔ℎ𝑡 𝑟𝑒𝑡𝑎𝑖𝑛𝑒𝑑 𝑖𝑛 𝑐𝑜𝑙𝑢𝑚𝑛 4
To calculate the cumulative percent of aggregate retained on the nth sieve (Percent finer),
𝑃𝑒𝑟𝑐𝑒𝑛𝑡𝑎𝑔𝑒 𝑝𝑎𝑠𝑠𝑖𝑛𝑔(%) = 100 − ∑ 𝑅𝑛 𝑜𝑟 100 − 𝑐𝑜𝑙𝑢𝑚𝑛 6
After calculating all the needed requirements, a graph of sieve size against total passing was
plotted. The graph is known as a grading curve.
ANALYSIS AND DISCUSSION
(By Afnan Munir Bin Mohd Khairi 23779)
Based on the experiment,we can determine the particle size distribution of fine and coarse
aggregate by sieving.The Fineness Modulus is the index number to determine the average size
of the particles in the fine and coarse aggregates. FM is the sum of the total percentages retained

on each specified sieve divided by 100.The higher the FM,the coarser the aggregate.Fine
aggregate affect many concrete properties,including workability.
Based on the result above,the FM is the cumulative percentage retained on standard size 0.15
mm(fine aggregate),2.36 mm(coarse aggregate) and above divided by 100.The cumulative
percentage retained on each sieve is added and subtracted by 100 to give the value for fine
aggregate.After the calculation,the value FM of fine aggregate is 3.01 and coarse aggregate is
3.71.The FM for the fine aggregate should be lower than the coarse aggregate.But looking based
on the result,the FM for both the aggregate is not much differ from each other.This is mainly due
to the coarse aggregate used during our lab has small gravels.
Reliability
1. Some suspended solid was left in the sieve make the reading inaccurate.
2. The aggregates contain some water, and this make the weight greater than it is supposed
to be.
3. The weighing machine is not calibrated to zero.
Modification
1. Blow away all suspended solid in the sieve and make sure none are left.
2. Dry the aggregate thoroughly in the drying oven with required temperature.
3. Press the zero button before start to weight the aggregates or sieves.
(Ashikin Mastura 23859)
From carrying out the experiment, we were able to determine the particle size distribution of
fine and coarse aggregates by sieving. This test method is used to determine the grading of
materials proposed for use as aggregates or being used as aggregates. Therefore, the gradation
gives an indirect measure if the workability and average particle size. The degree of gradation
will decide about the sand to be used which is also known as fineness modulus.

Fineness modulus (F.M.) of sand (fine aggregate) and gravel (coarse aggregate) are the index
number which represents the mean size of the particles in sand. The F.M. is the cumulative
percentage retained on standard sieve 0.15 mm (for fine aggregate), 2.36 mm (for coarse
aggregate) and above divided by 100. The cumulative percentage retained on each sieve is added
and subtracted by 100 gives the value of fine aggregate. From the equation, the value F.M. for
fine aggregate is 3.01 and for coarse aggregate is 3.71. For fine aggregate, the F.M. should be
lower than the fineness modulus of coarse aggregate. Although, there are not much difference
in the values obtained for F.M. between the two aggregates this is mainly due to the aggregate
used was a combination of various sizes. This shows our during lab session, the coarse aggregate
used has many small size gravels.
Sieve analysis is important by determining and knowing the fineness or the particle size
distribution of fine and coarse aggregates. Thus, Fineness Modulus is an index number to
determine the average size of the particles in the fine and coarse aggregates.
From the sieve analysis for fine aggregates, the fineness modulus is 3.01. It means the
average value of aggregate is in between 3rd and 4th sieve without counting the pan starting from
the bottom to the top. Thus, it means that the average aggregate size for fine aggregates is in
between 600 µm and 1.18 mm. Besides, this fine aggregate is categorized under ‘coarse sand’ as
its fineness modulus value is in between 2.9 – 3.2.
From the sieve analysis for coarse aggregates, the fineness modulus is 3.71. It means the
average value of aggregate is in between 3rd and 4th sieve without counting the pan starting from
the bottom to the top. Thus, it means that the average aggregate size for coarse aggregates is in
between 5 mm and 10 mm. This is because most of the coarse aggregate contained size of small
particles. By right, fineness modulus of coarse aggregates should range between 5.5 and 8 and
the size of particles should be around 20 mm. However, the coarse aggregate observed in our

experiment had many small size aggregate. Therefore, the fineness modulus and size for coarse
aggregates were quite lower than the normal situation.
In contrast, the fineness modulus of coarse aggregate is slightly higher than fine
aggregate. From this comparison, the more fineness modulus value indicates that the aggregate
is coarser whereas the small value of fineness modulus indicates that the aggregate is finer. The
fineness modulus between coarse and fine aggregates do not have much difference because of
the aggregate itself is a combination of various size.
Reliability
1. There were some suspended solids in the sieve and causing the weighing of aggregates
reading inaccurate.
2. There were some water content in the aggregates and causing a greater weight than it
supposed to be.
3. Misplacement of sieve order causing the result less reliable.
4. Weighing machine was not calibrated to zero before weighing the aggregates or sieves.
Modification
1. Make sure there is no suspended solid or impurities left in the sieve.
2. Make sure the aggregates were dried in the drying oven with temperature required.
3. Make sure the sieve order is decreasing in size from top to bottom.
4. Press the ‘zero’ button on the weighing machine before weighing the aggregates or
sieves.
Sieve analysis is used for finding the fineness or the size of aggregates for coarse and fine. In this
experiment, the Fineness Modulus is an index number to determine the average size of the
particles in the fine and coarse aggregates. The formula given for Fineness Modulus is the sum of
the total percentages retained on each specified sieve divided by 100.

After the sieve analysis have been done for fine aggregates, the fineness modulus is 3.01. So, we
can considered that the average size of fine aggregates is in the range is between 600 µm and
1.18 mm as it is in the third and fourth pan. The FM calculated is 2.9-3.2 which is categorized as
coarse sand for the sieve analysis for fine aggregates.
After the sieve analysis for the coarse aggregates, the fineness modulus is 3.71. The average size
of coarse aggregates is also the same which is at 3rd and 4th pan of the range size 5mm and 10mm.
For normality, the fineness modulus of coarse aggregates have to be from 5.5 – 8 and 20mm of
the particle size. So, we can say that most of the coarse taken have smaller particles.
The FM of coarse aggregates is higher than FM of fine aggregates. As obtained from the result,
the coarse aggregates have more fineness modulus while fine aggregates has less fineness
modulus.
Reliability
1. There are some impurities in the sieve that lead to wrong measurement of aggregates.
2. There are an excess water in the fine and coarse aggregates.
3. The weighing machine was not calibrated correctly.
4. The use of wrong sieve pan will affect the size of particle distribution.
Modification
1. We should have cleaned all the apparatus needed before conducting the experiment.
2. We should dry the aggregates under the sun to remove the excess water.
3. We have to press the zero button so that the scale will calibrated to zero.

4. We have to arrange the pan correctly based on size which is decreasing from top to
bottom.
A sieve analysis (or gradation test) is a practice or procedure used (in civil engineering) to assess
the particle size distribution (also called gradation) of a granular material. The size distribution is
often of critical importance to the way the material performs in use.
From this experiment, the sieve analysis for fine aggregates were observed and the fineness
modulus was 3.01 that means the aggregate average value is between 3rd to 4th sieves counting
from the bottom without counting the bottom pan.
Which means our average fine aggregate size is 600 µm and 1.18 mm, thus it is stated to be a
coarse sand as the fineness modulus is 2.9 – 3.2.
For the coarse aggregate, the fineness modulus is 3.71 that means the aggregate average value
Is between 3rd and 4th sieve counting from the bottom without counting the bottom pan.
Which means that the aggregate size for coarse aggregates is between 5mm to 10mm, we can
see in the laboratory that our coarse aggregate is contained of small particles/size.
The higher the fineness modulus value, the higher it is categorized under coarse aggregate, the
lower the fineness modulus value the close it is for being categorized as fine aggregate, thus in
this experiment we can observe that our fineness modulus for coarse aggregate is a bit higher
than the fine aggregate.
Reliability
1. Some dirt and impurities in sieve closing the holes which lead to some aggregate not
passing through.
2. The aggregate was not fully dried as there was some water in it.
3. The weighing machine is not set to zero.

Modification
1. Make sure to clean the sieve and open the closed holes to insure that your result is
more accurate.
2. Make sure to dry the aggregates so no extra weight been added on while weighing the
aggregates
3. Make sure before weighing the aggregate to set the weighing machine to zero.
Aggregate gradation (sieve analysis) is the distribution of particle sizes expressed as a percent of
the total dry weight. Gradation is determined by passing the material through a series of sieves
stacked with progressively smaller openings from top to bottom and weighing the material
retained on each sieve.
Fineness Modulus is calculated from the sieve analysis. It is defined mathematically as the
sum of the cumulative percentages retained on the standard sieves divided by 100. In fineness
modulus, the finer the material the more the water demand is. It is used for the purpose of
estimating the quantity of coarse aggregate to be used in the concrete mix design.
From the results, Fineness modulus of fine aggregate is 3.01. This shows the average value
of aggregate falls in between the 3rd sieve and 4th sieve. This also means that the average
aggregate size is in between 0.6 mm and 1.18 mm. Fineness modulus of coarse aggregate is 3.71.
Therefore, the most of aggregate falls in between the 3rd sieve and 4th sieve which means that
the average aggregate size is in between 5.00 mm and 10.00 mm.
The F.M. of fine aggregate should be lower than the fineness modulus of coarse
aggregate. Even so, the different are not much in the values obtained for F.M. therefore this is
still acceptable. This might because the coarse aggregate have more aggregate of smaller in size.

Reliability
1. Some impurities stuck at the sieve especially the one with smaller holes.
2. The aggregate were not fully dried can cause inaccuracy while weighing.
3. The weighing machine is not set to zero.
Modification
1. Make sure to clean the sieve’s hole before starting the experiment.
2. Make sure to dry the aggregates so no extra weight is added on while weighing the
aggregates
3. Press the ‘zero’ button before start to weigh.
CONCLUSION
Throughout this experiment, we managed to understand the test method which covers the
determinations of the particle size distribution of fine and coarse aggregates by sieving. A
weighed sample of dry aggregate was separated through a series of sieves of progressively
smaller openings for determination of particle size distribution. The importance of this
experiment is to vary different sand or gravel to create a strong concrete. This aggregate gives
volume to the concrete around the surface of which the binding material adheres in the form of
a thin film. In theory the empty pockets in the coarse aggregate is filled up with fine aggregate
and again the empty pockets in the fine aggregate is filled up with the binding materials.

AGGREGATE IMPACT VALUE TEST (AIV)
OBJECTIVE
The method of the test covers the procedures for determining the aggregate impact value of
coarse aggregate. The ‘Aggregate Impact Value gives a relative measure of the resistance of an
aggregate to sudden shock or impact, which in some aggregates differs from its resistance to a
slow compressive load.
APPARATUS
Aggregate impact testing machine consist of a circular base over which 2 vertical guides stand.
The hammer which is provided with a locking arrangement can be raised to fall freely down the
vertical guides. The height of fall can be adjusted through 300mm + 5mm. Supplied complete
with a metal measure 75mm diameter, ∅ x 50mm deep and tamping rod 230mm long and 10mm
dia.
PREPARATION OF TEST SAMPLE
a. The test sample shall consist of aggregate the whole of which passes a 12.5mm standard
sieve and is retained on a 10 mm standard sieve. The aggregate comprising the test
sample shall be dried in an oven for a period of 4 hours at a temperature of 100C – 110C
and cooled.
b. The cylindrical steel measure shall be filled about 1/3 rd full with the aggregate and
tamped with 25 strokes of the rounded end of tamping rod. A further similar quantity of
aggregate shall be added and a further tamping of 25 strokes given. The measure shall
finally be filled to overflowing, tamped 25 times and the surplus aggregate struck off,
using the tamping rod as a straight edge. The net weight of the aggregate in the measure

shall determined to the nearest gram (Call it weight A) and this weight of an aggregate
shall be used for the duplicate test on the same material.
PROCEDURE
1. The impact machine was rested without wedging or packing upon the level plate. Block
or floor, so that it is rigid and the hammer guide column was vertical.
2. The cup was to be fixed in position on the base of the machine and the whole of the test
sample was placed in it and was compacted by a single tap of 25 strokes of the tamping
rod.
3. The hammer was raised until its lower face to 380 mm above the upper surface of the
aggregate in the cup and was allowed to fall freely onto the aggregate. The test sample
was subjected to a total of 15 such blows each being delivered at an interval of not less
than 1 second.
4. The crush aggregate was then be removed from the cup and the whole of its sieved on
the 2.36 mm standard sieve until no further significant amount passes 1 minute. The
fraction passing the sieve was weighed to an accuracy of 0.1 g (Weight B). The fraction
retained on the sieve was also weighed (Weight C) and the total weight (B+C) should be
less than the initial weight (Weight A) by more than 1 g, the result shall be discarded as
fresh test made. Two tests were conducted.
CALCULATIONS
The ratio of the weight of fines formed to the total sample weight in each test shall be expressed
as a percentage, the result being recorded to the first decimal place.
𝐴𝑔𝑔𝑟𝑒𝑔𝑎𝑡𝑒 𝐼𝑚𝑝𝑎𝑐𝑡 𝑉𝑎𝑙𝑢𝑒 =
𝐵
𝐴
× 100

Where A = Total weight of the sample
B = Fraction passing 2.36 mm after crushing
The mean of the two results shall be reported to the nearest whole number as the aggregate
impact value of the tested material.
From carrying out the experiment, results were obtained and recorded as shown below:
Weight of cylinder = 905 g
Weight of cylinder + aggregate = 1211 g
Amount of aggregate = (1211 – 906) g
= 306 g
Weight of sample passing + Pan = 272 g
Weight of Pan = 230 g
Weight of sample passing = (272 – 230) g
= 42 g
Weight of sample retained on + 2.36 mm sieve = 700 g
Weight of 2.36 mm sieve = 438 g
Weight of sample retained on 2.36 mm sieve = (700 – 438) g
= 262 g

Sampl
e no.
Weight of
sample, A (g)
Weight of
sample
passing 2.36
mm, B (g)
Weight of
sample
retained on
2.36 mm, C (g)
Aggregate Impact
Value
Type of
aggregat
e
1 306 42 262 42
306
× 100 = 14 % Excellent
DISCUSSION
The objective of Aggregate Impact Value Test(AIV) is to determine the impact value or the
toughness of coarse aggregate to resist impact.Due to the movement of vehicles on the road,the
aggregates are subjected to impact which causes them to break into pieces.So,the aggregates
have to have the sufficient toughness to resist their disintegration due to impact.
In this experiment, the impact value of an aggregate can be calculated by calculating the
percentage loss of weight particles passing 2.36mm sieve by means of 15 blows of standard
hammer drop.From the data obtained in our experiment,we can see that the weight of the
aggregates are losing by 14%.Based on the Aggregate Impact Standard,we can say that our
aggregates are strong.The resistance in impact can be increased by using well-cubical stones than
flaky and elongated stones.
Reliability
1. There was some loss in weight of aggregate when pouring it into the sieve due to human
error.
2. There were some suspended solid left in the sieve which caused higher value in mass.
3. Weighing is not properly calibrated and will result to zero error.

Civil_Engineering_Materials_FULL_Lab_Rep.pdf

Civil_Engineering_Materials_FULL_Lab_Rep.pdf

Recommended

Recommended

More Related Content

Similar to Civil_Engineering_Materials_FULL_Lab_Rep.pdf

Similar to Civil_Engineering_Materials_FULL_Lab_Rep.pdf (20)

Recently uploaded

Recently uploaded (20)

Civil_Engineering_Materials_FULL_Lab_Rep.pdf