Sieve analysis is carried out for the determination of particle size distribution in the soil and performed as per IS 2386 Part-1
Apparatus:
Sieves of various sizes are shown below and shall conform to IS 460-1962
Type
Sieve Designation
Square hole,
Perforated Plate
80 mm, 63 mm, 50 mm, 40 mm, 31.5 mm,
25 mm, 20 mm, 16 mm, 12.5 mm, 10 mm,
6.3 mm, 4.75 mm
Fine mesh,
Wire Cloth
3.35 mm, 2.36 mm, 1.18 mm, 600 microns,
300 microns, 150 microns, 75 microns
Sample:
The weight of the sample available shall not be less than the weight given below.
Maximum size present
in substantial
proportions
(mm)
Minimum weight
of sample
(KG)
63
100
50
100
40
50
25
50
20
25
16
25
12.5
12
10.5
6
6.3
3
Procedure
- Dry the sample, if necessary at room temperature or by heating them at a temperature of $100^\circ C$ to $110^\circ C$ and clean the sieves if required.
- Weigh the sample and sieve it successively on the appropriate sieves starting from the largest.
Each sieve shall be shaken separately over a clean tray until not more than a trace passes through it but in no case less than 2 minutes.
- Break the lumps of fine materail, if any, by gentle pressure with a finger against the side of the sieve.
- Clear the sieve opening with a light brushing on the underside of the sieve.
- After the completion of sieving process, wiegh the aggregates retained on each sieve.
Note: Mechanical Sieving may be used but care should be taken to ensure that sieving is complete and the time for sieving should not be less than 10 minutes.
Result
- The cumulative percentage by weight of the total sample passing each of the sieves, to the nearest whole number.
- The percentage by weight of the total sample passing one sieve and retained on the next smaller sieve, to the nearest 0.1 percent.
- The results of sieve analysis may be recorded graphically on the chart for recording sieve analysis as shown below.
Wet Analysis
This method of test deals with the procedure for determining the total quantity of material finer than 75-micron IS Sieve in aggregates by washing.
Apparatus
- Balance
The balance or scale shall be of sufficient capacity and sensitivity and shall have an accuracy of 0.1 percent of the weight of the test sample.
- Sieve
A nest of two sieves, the lower being 75-micron IS Sieve and the upper approximately 1.18-mm IS Sieve (see IS :460-1962).
- Container
A pan or vessel of a size sufficient to contain the sample covered with water and to permit of vigorous agitation without inadvertent loss of any part of the sample or water.
- Oven
An oven of suflicient size capable of maintaining an uniform temperature of $110 \pm 5^\circ C$.
Sample
The test sample shall be selected from the material which has been thoroughly mixed and which contains sufficient moisture to prevent segregation. A representative sample, sufficient to yield not less than the appropriate weight of the dried material, as shown below, shall be selected:
Maximum nominal
size of aggregate (mm)
Minimum weight
of sample
(KG)
4.75
0.5
10
2
20
2.5
40 or over
5
Procedure
- Dry the sample at a tempeature of $110 \pm 5^\circ C$ and weigh it to the nearest 0.1 percent.
- Place the dried sample in a container and add water to cover it agitate it vigorously.
The agitation shall be sufficiently vigorous to result in a complete separation of fine aggregates (smaller than 75-micron) from coaser particles and bring the fine aggregates to suspension.
Care should be taken to avoid decanatation of coarse aggregate. This process is repeated until the wash water is clear.
- Immediatley pour the wash water over the nested sieve arranged with the coarser siever on the top.
- Dry the washed aggregate retained on the nested sieve at a temperature not more than $110 \pm 5^\circ C$ and weigh it to the nearest 0.1 percent.
Calculation
The amount of material passing 75-micron sieve is calculated from ,
$A=\frac{B-C}{B} \times 100$
Where
$A=$ Percentage of material finer than 75-micron
$B=$ Original dry weight
$C=$ Dry weight after washing
| Type | Sieve Designation |
|---|---|
Square hole, Perforated Plate |
80 mm, 63 mm, 50 mm, 40 mm, 31.5 mm, 25 mm, 20 mm, 16 mm, 12.5 mm, 10 mm, 6.3 mm, 4.75 mm |
Fine mesh, Wire Cloth |
3.35 mm, 2.36 mm, 1.18 mm, 600 microns, 300 microns, 150 microns, 75 microns |
Maximum size present in substantial proportions (mm) |
Minimum weight of sample (KG) |
|---|---|
| 63 | 100 |
| 50 | 100 |
| 40 | 50 |
| 25 | 50 |
| 20 | 25 |
| 16 | 25 |
| 12.5 | 12 |
| 10.5 | 6 |
| 6.3 | 3 |
Each sieve shall be shaken separately over a clean tray until not more than a trace passes through it but in no case less than 2 minutes.
The balance or scale shall be of sufficient capacity and sensitivity and shall have an accuracy of 0.1 percent of the weight of the test sample.
A nest of two sieves, the lower being 75-micron IS Sieve and the upper approximately 1.18-mm IS Sieve (see IS :460-1962).
A pan or vessel of a size sufficient to contain the sample covered with water and to permit of vigorous agitation without inadvertent loss of any part of the sample or water.
An oven of suflicient size capable of maintaining an uniform temperature of $110 \pm 5^\circ C$.
Maximum nominal size of aggregate (mm) |
Minimum weight of sample (KG) |
|---|---|
| 4.75 | 0.5 |
| 10 | 2 |
| 20 | 2.5 |
| 40 or over | 5 |
The agitation shall be sufficiently vigorous to result in a complete separation of fine aggregates (smaller than 75-micron) from coaser particles and bring the fine aggregates to suspension.
Care should be taken to avoid decanatation of coarse aggregate. This process is repeated until the wash water is clear.
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