Dry Sieve Report

1.0 OBJECTIVE

The sieve analysis determines the grain size distribution curve of soil sample by passing them

through a stack of sieves of decreasing mesh opening sizes and by measuring the weight

retained on each sieve. The sieve analysis is generally applied to the soil fraction larger than

75µm.

2.0 LEARNING OUTCOME

At the end of this experiment, students are able to:

2.1 Understand the methods used to determine the size of soil particles in the laboratory;

2.2 Carry out the calculation processes used in particle size determination;

2.3 Understand the methods used to determine the consistency properties of fine grained

soils in the laboratory;

2.4 Carry out the calculation and plotting processes used in consistency limit methods of

classification;

2.5 Appreciate the way in which particle size and consistency properties are used to

classify and predict the probable behavior of soils and also to indicate the type of tests

needed to assess their engineering characteristics.

3.0 THEORY

(BS1377 : Part 2:1990:9.3), Sieving can be performed in either wet or dry conditions.

Dry sieving is used only for soil with a negligible amount of plastic fines such as

gravels and clean sands, where as wet sieving is applied to soils with plastic fines.

According to the British Standard, dry sieving may be carried out only on materials

for which this procedure gives the same results as the wet-sieving procedure. This

means that it is applicable only to clean granular materials, which usually implies

clean sandy or gravelly soils that is, soils containing negligible amounts of particles

of silt or clay size. Normally the wet-sieving procedure should be followed for all

soils. If particles of medium gravel size or larger are present in significant amounts,

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the initial size of the sample required may be such that riffling is necessary at some

stage to reduce the sample to a manageable size for fine sieving.

BS 1377: 1990, allows either wet or dry sieving to be used, but the wet method is

preferred. After oven drying, the test sample mass is determine before being separated

into two parts, the first comprises that retained on a 20 mm sieve and the second that

passing 20 mm. That greater than 20 mm is dry sieves, while that smaller is wet sieve

prior to being re-sieved dry. The sieves used are generally chosen from the range (in

mm) of 75, 63, 50, 37.5, 28, 20, 14, 10, 63.5, 3.35, 2, 1.18, 0.6, 0.425, 0.3, 0.212, 0.15

and 0.063. The mass retained on each sieve is recorded, from which the percentage of

the sample passing each sieve can be calculated. Material passing the 63 micron (0.063

mm) sieve is retained for a fine particle analysis, if the amount justifies the further test.

The combined results of the coarse and fine analyses are plotted on a semi-logarithmic

graph of the form show in Figure 1.0, to give the particle size distribution curve.

Figure 1 : Particle size grading curves of some typical soil

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4.0 TEST EQUIPMENTS

1. Series of standard sieves with opening ranging from 7.5cm to 75m including a cover

plate and bottom pan.

2. Test sieve having the following aperture size 10mm, 6mm, 1mm, 0.6mm, 0.3mm,

0.15mm, 0.063 mm.

3. Mechanical sieve shaker

4. Balances sensitive 0.5g

5. Soft wire brush

Figure 2 : Typical stack of sieve for grain size analysis

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5.0 TEST PROCEDURE

1. Write down the weight of each sieve as well as the bottom pan to be used in

the analysis.

2. Record the weight of the given dry soil sample.

3. Make sure that all the sieves are clean, and assemble them in the ascending

order of sieve numbers. Place the pan below #200 sieves. Carefully pour the soil

sample into the top sieve and place the cap over it.

4. Place the sieve stack in the mechanical shaker and shake for 10 minutes.

5. Remove the stack from the shaker and carefully weigh and record the

weight of each sieve with its retained soil. In addition, remember to

weight and record the weight of the bottom pan with its retained fine

soil.

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6.0 DATA SHEET:

Sieve no.

size (mm)

Mass

Retained (g)

Mass

Passing (g)

Cumulative

Percentage passing (%)

10.000 0 500 100

6.300 50.8 449.2 90

1.180 66.4 382.8 77

0.600 236.1 146.7 29

0.300 84.8 61.9 12

0.150 32.3 29.6 6

0.063 16.4 13.2 3

Pan 10.3

How to calculate mass passing

Mass passing when sieve no size 10.00mm is (500 - 0) = 500g

Mass passing when sieve no size 6.30mm is (500 – 50.8) = 449.2g

Mass passing when sieve no size 1.18mm is (449.2 – 66.4) = 382.8g




Mass passing when sieve no size pan is (29.6 – 16.4) = 13.2g

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How to calculate cumulative percentage passing ( % )

Formula : mass passing x 100

Mass of dry sample

Sieve no size = 10.00mm

Cumulative percentage passing : 500 x 100

500

: 100%


Cumulative percentage passing : 449.2 x 100

500

: 90%



500

: 77 %



500

: 29%



500

6

: 12%



500

: 6%



500

: 3%

% Passing = 100 - ∑ % Retained.

Mass of dry sample = 500 gram

Plot particles size distribution chart.

Cu=d60

d10 = ____________ .

C c=d

302

d60 d10 =___________.

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0.63 0.15 0.3 0.6 1.18 6.3 100

20

40

60

80

100

120

TABURAN SAIZ ZARAH

Perjumlahan Kumulatif (%)

7.0 QUESTIONS

1. What is the purpose of grain size analysis?

The purpose of sieve analysis is to determine the grain size distribution curve if

soil sample by passing them through a stack of sieves of decreasing mesh opening sizes

and by measuring the weight retained on each sieve. The sieve analysis is generally

applied to the soil fraction larger than 75m.

Meanwhile, student would be able to used methods that are thought in lecture

class determine the size of soil particles in the laboratory. Moreover, students will

understand a lot more on a method used to determine the consistency properties of fine

grained soils in the laboratory, and even this method will be helpful in the future when

they work.

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Nevertheless, grain size analysis have its own type of graph, and those who had

settle the calculation and plotting graph process for this experiment, they absolutely will

master on consistency limit methods of classification. Lastly, student also should

appreciate this analysis experiment for showing the way in which particle size and

consistency properties are used to classify and predict the probable behavior of soils and

also to indicate the type of test needed to assess their engineering characteristics.

2. Under what conditions should you use wet sieving instead of dry sieving?

Sieving can be performed in either wet or dry conditions. Dry sieving is used only

for soil with a negligible amount of plastic fines such as gravels and clean sands, where

as wet sieving is applied to soils with plastic fines.

According to the British Standard, dry sieving maybe carried out only on

materials for which this procedure gives the same result as the wet-sieving procedure.

This means that it is applicable only to clean granular materials, which usually implies

clean sandy or gravelly soils that is, soils containing negligible amounts of particles of

silt or clay size. Normally the wet-sieving procedure should be followed for all soils. If

particles of medium gravel size or larger are present in significant amount, the initial size

of the sample required may be such that riffling is necessary at some stage to reduce the

sample to a manageable size for fine sieving.

3. What is the smallest and largest mesh openings used in practice for determining

grain size distribution?

For this dry sieving experiment, the kind of opening that we used are the series of

standard sieves and opening ranging from 7.5cm- 75µm including a cover plate on the

top of those sieves and a bottom pan. Then, to shake those sieves, we used the

mechanical sieves shaker and vibrate those sieves by layers for 10 minutes.

4. Is it possible to carry out a sieve analysis on a sample of clay?

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A sieve analysis is a practice or procedure used to assess the particle size

distribution of a granular material. The size distribution is often of critical importance to

the way the material performs in use. A sieves analysis can be performed on any type of

non-organic or organic granular materials including sand, crushed rock, clay, granite,

feldspars, coal and 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 method. So, we can see that we can

absolutely carry out a sieves analysis on a sample of clay.

Most sieves analysis is carried out dry. But there are some applications which can

only be carried out by wet sieving. This is the case when the sample which has to be

analyzed is e.g. a suspension which must not be dried or when the sample is very fine

powder which tends to agglomerate (mostly < 45µm) in a dry sieving process this

tendency would lead to a clogging of the sieve meshes and this would make a further

sieving process impossible.

A wet sieving process is set up like a dry process: the sieves stack is clamped on

to the sieves shaker and the sample is placed on the top sieve. Above the top sieves a

water-spray nozzle is placed which supports the sieving process additionally to the

sieving motion. The rinsing is carried out until the liquid which is discharges through the

receiver is clear. Sample residues on the sieves have to be dried and weighted. When it

comes to wet sieving it is very important not to charge in its volume (no swelling,

dissolving or reaction with the liquid).

5. Classify the type of soil that you use in the laboratory according to BS 5930.

From the graph that been plotted with the data have, we can classify the type of

soil that have been in the lab experiment. Here, we can probably saw that the soils used

are contained of coarse sand and fine gravel. It is because that the dots that plotted in the

graph are mostly in the coarse sand and fine gravel area.

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8.0 SOIL CLASSIFICATION SYSTEM (BS 5930)

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Dry Sieve Report

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Transcript of Dry Sieve Report