KB2022
– Design and Materials
Laboratory
Report
Module Leader
Dr Mohammadali Rezazadeh
Contents
Page…………………………………………. Aggregate Sampling
Page…………………………………. Batching Concrete and
Determining Slump
Page……………………………………………Compressive and
Rebound Hammer Non-Destructive Tests on Concrete Cubes
Page…………………………………………Flexural Bending Tests
on Plain and Reinforced Beams
Page…………………………………………. Timber Beams Test
Page………………………………………………. Steel Tensile Test
Page…………………………………………………References
Test 1 - Aggregate Sampling
In this test we will look at both the coarse and the
fine aggregate in a sample and determine the contents via the shape and the
size using sieve analysis only. The
purpose for this test is to classify what the aggregate we are using and can be
used in different applications such as making concrete.
Method
First, we would
weigh each large sieves from the large sieve set (the opening sizes are
>4.75mm) including the pan using a balance and record each of the weights on
a table.
Next, we will place the bucket on the balance and then
zero the weight so that we can measure the aggregate weight. We will take a
random batch of 12kg coarse aggregate and weigh it to make sure its 12kg. Using
a ruffle box, we evenly pour the sample into the box so it can separate the
weight in half and taking half of the weight we pour it one more time to get
approximately 3kg and weigh the sample and record it.
Making sure that the order of the larger sieves is
correct (largest at top and smallest at bottom) we will then pour the sample
aggregate evenly in the larger sieves, place the lid on top of the sieves.
Next, we would place the sieves in a vibration machine
where it will separately apply force onto each sieve so the aggregate can fall
to it’s determined sieve, we wait for 10-20 minutes.
Then we would take each of the sieves including the
separated aggregate and weigh them again and record each weight of the
aggregate and sieve on a table.
We would then do the same with the fine aggregate but
the series of sieves would be less than or equal to 4.75mm opening size. Weigh
each of the sieves and record the weight taking notice on the order size of the
sieves.
Take a beaker
and place on the balance and zero the weight of the beaker. Then we need to
scoop 3kg of the fine aggregate without using the ruffle box due to its size.
Weigh the aggregate and record it.
Pour the fine aggregate on the small sieve tower and
place a lid. Then we place the sieve in a smaller vibration machine so the
aggregate can get to its sieve opening size and wait for 10-20 minutes. Take
the sieves out of the machine and then weigh each of the sieves again including
the pan and record the weight of the aggregate for the specified opening size.
After calculating the mass and the percentage of the
aggregate passing through each sieve size for coarse and fine aggregate we then
draw a particle distribution curve each for the fine and coarse aggregate due
to the size differences.


Then we can calculate the uniformity coefficient (
) for
both the fine and coarse aggerate distributions so we can classify the
aggregate that we sampled.
Coarse Aggregate
where Cu < 4 then the coarse
aggregate sample is uniformly graded, in this case the aggregate sample has a
small range of particle sizes.
Fine Aggregate
Where Cu > 6 then the fine
aggregate sample is well graded fine aggregate within the sample collected in
the test.
We then add another column in the table of values and using each
percentage passing we take 100 from this and finding the total we can calculate
the fineness modulus for fine/coarse aggregate.
Coarse Aggregate
Fineness Modulus: ![]()
Fine Aggregate
Fineness Modulus: ![]()
Data
Fine Aggregate
|
Sieve
size and weight |
Mass
retained on each sieve |
Total
mass passing each sieve (g) |
Percentage
passing each sieve |
100-PP% |
||
|
Size (mm) |
Weight
(g) |
Pan
+ Mass |
Mass |
Total
Mass |
|
|
|
3.35 |
516.8 |
547.9 |
31.1 |
267.2 |
89.57% |
10.43 |
|
2.36 |
479.5 |
507.5 |
28.0 |
239.2 |
80.19% |
19.81 |
|
1.18 |
440.6 |
502.0 |
61.4 |
177.8 |
59.60% |
40.4 |
|
0.60 |
392.8 |
449.6 |
56.8 |
121.0 |
40.56% |
59.44 |
|
0.425 |
379.3 |
403.0 |
23.7 |
97.3 |
32.62% |
67.38 |
|
0.300 |
369.2 |
391.6 |
22.4 |
74.9 |
25.11% |
74.89 |
|
0.212 |
359.2 |
386.5 |
27.3 |
47.6 |
15.96% |
84.04 |
|
0.150 |
282.6 |
325.5 |
42.9 |
4.7 |
1.58% |
98.42 |
|
Pan |
245.7 |
250.4 |
4.7 |
0.0 |
0.0% |
100 |
|
|
|
|
|
|
|
|
|
Total |
|
|
298.3 |
|
|
554.81 |
Coarse Aggregate
|
Sieve
size and weight |
Mass
retained on each sieve |
Total
mass passing each sieve (g) |
Percentage
passing each sieve |
100-PP% |
||
|
Size (mm) |
Weight
(g) |
Pan
+ Mass |
Mass |
Total
Mass |
|
|
|
37.5 |
1447.5 |
1447.5 |
0.0 |
3115.0 |
100% |
0 |
|
28.0 |
1375.5 |
1375.5 |
0.0 |
3115.0 |
100% |
0 |
|
20.0 |
1330.0 |
1492.5 |
162.5 |
2952.5 |
94.78% |
5.22 |
|
14.0 |
1170.5 |
2553.0 |
1382.5 |
1570.0 |
50.40% |
49.60 |
|
10.0 |
1163.0 |
2377.5 |
1214.5 |
355.0 |
11.40% |
88.60 |
|
6.3 |
1019.5 |
1312.0 |
292.5 |
63.0 |
2.02% |
97.98 |
|
5 |
993.0 |
1007.0 |
14 |
49.0 |
1.57% |
98.43 |
|
Pan |
691.5 |
740.5 |
49 |
0.0 |
0.0% |
100 |
|
Total |
|
|
3115.0 |
|
|
439.83 |
Conclusion
Coarse aggregate
is mostly made up of gravel and broken stones, whilst fine aggregate is mostly
made up of sand. The above-shown particle size distribution curve has a severe
slope. This signifies that the coarse aggregate is weakly graded, which means
that it is consistently graded and has very little variation in particle size
on the sample. The fine aggregate particle-size distribution curve is
characterized by an S-curve; the fine aggregates are highly graded, which means
they have various sizes in that sample. The particle gradation is uniform,
ranging from coarsest to finest. Because the aggregate sizes interlock
effectively, the strength of the concrete will be much enhanced when such
aggregate is utilized for concreting. Our finding is further corroborated and
backed up by computer data, which show that the coefficients of uniformity and
gradation are 6.8 and 1.04 for highly graded aggregates, respectively, and 1.57
and 1.06 for poorly graded coarse aggregates. However, there are some
significant differences since we employed manual sieves; this gap is
understandable because the manual technique is unsuccessful due to the variety
in energy used. Finally, the conclusion based on the interpretation of the
manual findings is a six, which is similar to the conclusion based on the
calculated coefficients of uniformity and gradation.
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