Fine aggregate size as per is code 383




Sieve analysis for Fine Aggregate -Introduction 
       Before construction sieve analysis of fine aggregate is most important because fine aggregate divided into four parts zone-i, zone-ii, zone-iii and zone -iv. For concrete using fine aggregate  is zone -ii and zone-iii As per IS code 383:1970. Brick work and plastering  purpose using fine aggregate is zone-iii and zone-iv.

Why Sieve analysis ? 
      as per  is code 456:2000 doing concrete water and cement and fine aggregate and course aggregate .fine aggregate is 40% out of total aggregate in concrete. fine aggregate size  as per is code 383 is 4.75mm,2.36mm,1.18mm,600 micron,300 micron,150 micron. so all type of particle size in aggregate. so binding properly and no voids inside filling properly.


Frequency of testing
  1. Every 40cum of sand required in RCC work only.
  2. Every 80cum of fine aggregate.
Apparatus
  • sieve 10mm
  • sieve 4.75mm
  • sieve 2.36mm
  • sieve 1.18mm
  • sieve 600 micron
  • 300 micron
  • 150micron
  • weighing machine

The weight of sample shall not be less than as given bellow

Maximum size percent in substantial proportion (mm)

Maximum weight of sample for sieving (kg)

10

0.5

4.75

0.2

2.36

0.1

TEST PROCEDURE
      Sample should be at  an air dry condition. It shall be weighed and sieved on appropriate sieves starting with the largest. Each sieve shall be shaken separately not less than 2 minutes over a clean tray until not more than trace passes. material shall not be forced through the sieve by hand pressure. Light brushing of under side sieve is permitted.
      On completion sieve the material retained one each sieve together with any material cleaned form the mesh shall be weighted. 

Results  
  1. The cumulative percentage by weight of total sample passing each of the sieves,to the nearest whole number.
  2. The percentage by weight of the total sample passing on sieve an retained on the next smaller sieve to the nearest 0.1%.       
    As per is code 383:1786

Sieve size

Grading zone -i

Grading zone -ii

Grading zone -iii

Grading zone -iv

10mm

100

100

100

100

4.75mm

90-100

90-100

90-100

95-100

2.36mm

60-95

75-100

85-100

90-100

1.18mm

30-70

55-90

75-100

90-100

600 micron

15-34

35-59

60-79

80-100

300 micron

5-20

8-30

12-40

15-50

150 micron

0-10

0-10

0-10

0-15

 Note

  • When the grading falls out side the percentage limits of any particular grading zone other than 600 micron sieves by total not more than 5%, it shall be regarded as falling with in the respective zone. This 5% can be split up, for example it could be 1% on one sieve and 2% one another.
  • If grading falls out side the percentage limits against each is sieve after taken note (i) into , account , sand shall be screened and test shall be repeated with a new serial number in the register, Action taken for screening etc.
  • Fine aggregate conforming to grading zone -iv shall not be used for RCC, unless tests have been made to ascertain the suitability of proposed mixed proportion.
  • until and other wise specified sand used for preparing mortar for plaster work shall conform to IS 1542 and for masonry work it shall conform to IS 2116 
Example of zone-iii grading 

Weight of sample in gram

Is sieve size mm

Weight of retained in gram

Percentage of retained gram

Cumulative percentage of gram

Percentage of passing

Percentage of passing as per is 383

3000

10mm

0

0

0

0

100

 

4.75mm

68

2.26

2.26

97.73

90-100

 

2.36mm

37

1.23

3.49

96.51

85-100

 

1.18mm

127

4.23

7.72

92.27

75-100

 

600 mic

577

19.23

26.95

73.04

60-79

 

300 mic

1442

48.06

75.01

24.98

12-40

 

150 mic

728

24.26

99.27

0.72

0-10

 

pan

21

 

 

 

 

 


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