SMSieveAnal

The University of Toledo
Soil Mechanics Laboratory
1

Grain Size Distribution – Sieve Analysis

Introduction
The grain size distribution is a representation of the approximate distribution of soil grain sizes for a soil. The sieve analysis, also called mechanical method, measures the dry mass of soil retained on each sieve in a stack of sieves, where the sieve opening sizes vary from the largest to smallest going from the top to the bottom of the stack. All the soil particles retained on a particular sieve will have an ‘intermediate size’ or ‘average diameter’ that is smaller than the opening of the sieve above and larger than all the sieves below. Thus the individual particle sizes of the soil are not measured but the range of sizes (i.e. smaller than the sieve above and larger than the sieve retaining the particle) is determined. The grain size distribution is obtained by plotting the percent finer by dry mass, the percent of all the soil below a particular sieve, versus the log of the particle diameter, taken as the opening size of the sieve. A smooth curve is drawn to represent the grains size distribution. The grain size distribution is used to classify soils and to determine the suitability of soils for various engineering purposes.
Apparatus
1.
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5.
6.

Drying Oven
Mortar and pestle for pulverizing fine grained soils (optional)
Set of sieves with mesh openings approximately halved for each successive smaller size sieve (See table below.)
Wire and Soft Brush
Precision balance capable of measuring samples to 0.1 g.
Sieve shaker

Size or
Number
Lid
4
10
20
40
60
100
200
Pan

Opening mm 4.75
2.00
0.850
0.425
0.250
0.150
0.075

Note: Alternatively, other sieve sizes can be substituted for the above sieves.

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ASTM D 422 – 1963 (Reapproved 1998)

Sieve Analysis - 1

Procedure
A. Preparation (at least 24 hours before test)
1) Measure approximately 250 g. of a coarse-grained soil. The soil should have more than
95% passing the No. 4 sieve and less than 5%