grain size analysis

SIEVE ANALYSIS(IS 2720 PART4)

Sawanpreet SinghAnoop Singh

Engineering Soil Testing

Objectives

Classification of Soil

Coefficient of curvature Uniformity coefficient Fineness Modulus

Applications

Gradation of soil:Well gradedPoorly graded

Proportioning of soil for mix design

Design of filters

Theory

If more than 50% of sample is retained on IS Sieve 4.75mm,sample is gravel

If more than 50% of sample passes through IS Sieve 4.75mm,sample is sand

Theory

Coefficient of Curvature :

Cc = D302

D10 x D60

Between 1 -3 : Well graded gravel and sand

Theory

Uniformity Coefficient :

Cu = D60

D10

More than 4 - Well graded gravelMore than 6 – Well graded sand

(IS 1498 - 1970)

Theory

Fineness modulus (FM) :

sum of total percentage of the FM = sample retained on each sieve

100

2 – 4 : fine soil6.5-8 : coarse soil

Apparatus

Two set of sieves:

Set1: IS sieves of size 300mm, 80mm, 40mm, 20mm, 10mm, 4.75mmSet 2 : IS sieves of size 2mm,0.85mm,0.425mm,0.15mm,0.075mm

Mechanical Shaker Brush Oven Weigh balance

Procedure

For sample retaining on 4.75mm sieve ,Use set 1 – 5kg sample

For sample passing through 4.75mm sieve,Use set 2 – 1kg sample

Procedure

Clean all the sieves and pan properly with brush.

Arrange the sieves according to size, with pan at bottom and size increasing upwards.

Put the sample in top sieve and Place it in the shaker.Ensure that the sieves are held tightly in the shaker.

Procedure

Operate the shaker for 5-10 minutes.

Weight the material retained on each sieve to nearest 1 gram.

Precautions

While drying, the temperature of oven should not be more than 105°C because higher temperature may cause permanent change in 0.075mm material.

During shaking, soil sample should not be allowed to come out.

For plotting, percent finer should be determined with respect to total soil taken for initial analysis.

Observations and Calculations

IS Sieve2.36mm

Observations and Calculations

IS Sieve1.18mm

Observations and Calculations

IS Sieve0.600mm

Observations and Calculations

IS Sieve0.300mm

Observations and Calculations

IS Sieve0.150mm

Observations and Calculations

IS Sieve0.075mm

Observations and Calculations

Pan

Observations and Calculations

Observations and Calculations

Result

Thank You!!