Welcome to L1 Supply Networks
IS Sieve
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Percentage passing for
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Grading zone I
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Grading zone II
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Grading zone III
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Grading zone IV
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10 mm
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100
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100
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100
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100
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4.75 mm
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90-100
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90-100
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90-100
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90-100
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2.36 mm
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60-95
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75-100
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85-100
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95-100
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1.18 mm
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30-70
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55-90
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75-100
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90-100
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600 microns
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15-34
Sand is one of the basic raw materials used for construction. It is a fine aggregate that is either
extracted from natural sources or made artificially in factories by crushing bigger rocks or gravel.
Its size lies between 150 microns to 4.75 mm. Fine aggregate consists of natural sand, stone
dust, crushed sand, gravel, fly ash, and broken brick. It should be well-graded to ensure that all
its particles are of the same size.
Sand is mixed with concrete and is used to fill the voids between coarse aggregates. Sand helps
in increasing the workability of the concrete. It is used in brickwork, plastering work and RCC
work.
Quality testing of sand
Sand is considered ideal if it is durable, inert, clean and free from organic matter, and the
presence of iron pyrites, alkalis, salts or coal can affect the quality of concrete and cause
corrosion. The presence of harmful materials in the sand must not exceed 5%.
4 major tests are conducted to determine the quality of sand
1.Silt content test
2.Particle size distribution
3.Organic impurities test
4.Bulking of sand
Silt content test
Take some sand in a beaker and add a glass of water to it. Stir it well and wait for the mix to
settle down. Observe after an hour, and you’ll see that the clean sand has settled at the bottom
and a layer of silt containing clay particles or other impurities will be formed at the top.
The amount of silt in the sand shall not exceed 8%. The presence of clay can make the sand
cohesive and it is ideal for sand to have fewer traces of silt. If the silt is more than the
recommended amount, it should be washed to bring the silt within allowable limits.
Particle size distribution
It is also known as testing for the grade of sand. Fine aggregate is divided into 4 zones based on
its size. Sand is meant to be coarser for RCC works and plastering works it is meant to be finer.
The following table gives the details about different grades of sand
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