soil-report-1-ba7bk-ya-h

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Sieve analysis
 Introduction
Fig. 1. “Mechanical shaker”
A sieve analysis (or gradation test) is a practice or procedure used 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. A sieve analysis can be performed on any
type of non-organic or organic granular materials including sands, crushed rock, clays, granite,
feldspars, coal, soil, a wide range of manufactured powders, grain and seeds, down to a
minimum size depending on the exact method. Being such a simple technique of particle sizing,
it is probably the most common. Aggregates have definite effects on the properties of concrete
and their selection is important to the effective use of concrete. Sieve analysis is performed on
fine and coarse aggregates in order to determine the particle size and the distribution of
aggregates in specified amount of sample. A sieve analysis can be performed on any type of
non-organic or organic materials including sands, crushed stones, crushed gravel, clays, coil and
soil.
Fig. 2. “Balance with a sample on it”
 Objectives
The sieve analysis determines the grain size distribution curve of soil sample by passing
them through a stack of sieves of decreasing netting opening sizes and by measuring the
weigh tretamine on each sieve. determine the particle size and the distribution of
aggregates in specified amount of sample .And to Select sieves I.S specifications and
perform sieving, Obtain percentage of soil retained on each sieve, and Draw graph
between log grain size of soil and % finer.
 Methodology and Procedures
 A sample of fine aggregates were taken and measured by the balance. Its weight was
about 2002g.
 The sample was put on the stack of sieves, in descending order, starting with the sieve
opening of diameter 4.75mm till the smallest sieve of diameter 150μ or 0.15mm then a
pan.
 The stack of sieves was put on the mechanical shaker to separate the sizes of the fine
aggregates.
 The weight retained on each sieve and the pan was measured.
 Weigh each empty sieve and the pan.
 Nest the suitable sieves in order of decreasing size of opening from top to bottom. Place
the pan at the bottom of the set.
 Place the sample on the top sieve.
 Place the lid, and agitate the sieves in the mechanical shaker for about 5 minutes, or long
enough to distribute all the aggregate. .
 Weigh the sieves with the material retained.
 Determine the weight retained in each sieve. The total weight of the material after sieving
should check closely with the original weight of the sample.
 Calculate the percentage coarser than and the percentage passing, and draw the graph.
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 Results and graph
Total sample weight : 2002 gm
Sieve number
Opening
(mm)
Mass
Retained
(gm)
Total mass
Retained
Passing
Cumulative Ret. (%)
Re.
Percentage
4
10
20
40
60
80
100
200
4.75
2.36
1.25
0.6
0.3
0.15
0.075
pan
110
169.5
159
707
728
88
25.5
15
110
279.5
438.5
1145.5
1873.5
1961.5
1987
------------
1892
1722.5
1563.5
856.5
128.5
40.5
15
-
94.5055
86.039
78.0969
42.7822
6.41858
2.0229
0.7492
------
5.4945
10.961
21.9031
57.2178
93.558142
97.9771
99.2508
Sieve Analysis
100
90
80
passing percent %
70
60
50
40
Sieve Analysis
30
20
10
0
10
1
0,1
0,01
Sieve Diameter
1. Uniformity coefficient =D60/D10 = 0.85/0.3 =2.833
2. Coefficient of gradient = (D30)2/D10*D60 = 0.652 / 0.85*0.3 = 1.658 > 1
(well graded )
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 IN Conclusion
Finally, the goal of sieve analysis test is to determine the properties of the aggregate and to see
if it is appropriate for various civil engineering purposes such as selecting the appropriate
aggregate for concrete mixes and asphalt mixes as well as sizing of water production well
screens. And, to advantages of the sieve analysis include easy handling, low investment costs,
precise and reproducible results in a comparably short time and the possibility to separate the
particle size fractions.
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Liquid limit
 Introduction
Liquid limit (LL) is the water content inside the soil in percent, that makes the sample in a liquid
state. This test is performed on clay samples. The objective behind it is to compare it between
the code’s limitation to classify the sample. This can help to choose the suitable
recommendation to the foundation used in the building.
 Equipment
1-Casagrande’s liquid limit device
Fig 1 Casagrande’s liquid limit device
2-Grooving tool with gage length of 13 mm
Fig 2 Grooving tool
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3-4Cups
4-Spatula
5-Water bottle filled with distilled water
Fig 3 Pouring distilled water on the clay
6-Dry oven set at 110 °C
7-Weighing balance
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Fig 4 Balance with the cup and a sample on it
 Procedures
 Place prepared sample in the cup of the liquid limit device
 Draw the grooving tool through the sample along the symmetrical axis of the cup, holding
the tool perpendicular to the cup.
 Lift and drop the cup at a rate of around 2 drops per second
 Record the number of drops required to make the parts of the soil sample come into
contact for about 13 mm length
 Remove the slice of soil and place it into the cup to determine its water content
 Repeat these steps with another samples (around 4)
Liquid limit table
Sample #
Number
Mass of
of blow
cup (gm)
Mass of
Mass of
cup & wet cup & dry
Mass of
Mass of
Water
dry soil
water
content %
soil (gm)
soil (gm)
(gm)
1
37
17.5
86.5
70
52.5
16.5
31.4
2
40
16
56
44.5
28.5
11.5
40.3
3
24
20
72
58
38
14
36.8
4
22
17
68.5
65
48
3.5
7.29
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 Graph
Liquid limit
WC(%)
90,0%
Liquid limit
60,0%
30,0%
100
10
1
 Conclusion
By altering the water content of the soil and repeating the foregoing operations, obtain at least
4 readings in the range of less than and more than 25 blows. Don’t mix dry soil to change its
consistency. Liquid limit is the water content percentage at 25 blows, which in this case was
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Plastic limit test
 Introduction
Fig. 1 the sample used in test
The plastic limit of soil is water content of the soil below which it ends to be plastic. It begins to
crumble when rolled into threads of 3mm diameter and presented as a percentage of the weight of
the oven dried soil at which the soil can be rolled.
 Objectives
The aim of this experiment is to determine the samples of soil which the limit between plastic
state and semi plastic state. The plasticity index of a soil is the numerical difference between the
liquid limit and the plastic limit. It is the moisture content at which the soil is in a plastic state
 Equipment
1. Ground glass plate about 200mm x 150mm
2. Metallic rod 3mm diameter and 100mm long
3. Oven
4. Spatula
5. Vernier caliper
6. balance
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Fig. 2 the equipment used in plastic limit test
 Procedure
 Take about sample of the soil and roll it with fingers on a glass plate. The rate of rolling
should be between 80 to 90 strokes per minute to form a 3mm diameter.
 If the diameter of the rolled sample is less than 3mm, without any cracks appearing, it
means that the water content is more than its plastic limit and need to reduce water
content by rolling it again
 Repeat the process of alternate rolling and kneading until the thread crumbles
 Then we measure specimen weight
 Repeat the procedures three times with fresh samples of plastic soil each time
 Putting the specimens in oven for 24 hours
 Then calculate the plastic limit
Fig.3 sample after dried in oven
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 Calculations
Sl.
No.
1
Observations and Calculations
Sample .1
Sample .2
Sample .3
Sample.4
Mass of empty container (m1)
17
18
19
20
2
Mass of container + wet soil (m2)
18.5
19.5
20
21.5
3
Mass of container + dry soil (m3)
18
19
19.5
21
4
Water content = (m2- m3/ m3-m1)
*100%
0.5
0.5
1
0.8
The plastic limit = 57.1%
 Conclusion
The plastic limit is the water content at which a soil becomes too dry to be plastic. It used
together with the liquid to determine the plasticity index and It is recognized that the results are
subject to the judgment of the operator, and that some variability in result will occur. It is
convenient to carry out the test on a portion of the prepared material and through this experiment,
we managed to achieve the objective of this lab that is to measure the plastic limit to the given
soil sample
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