2. DETERMINATION OF SPECIFIC GRAVITY
OBJECTIVE
Determine the specific gravity of soil fraction passing 4.75 mm I.S sieve by Pycnometer.
NEED AND SCOPE
1-The knowledge of specific gravity is needed in calculation of soil properties like void
ratio, degree of saturation etc.
2-specific gravity of soil is an important parameter for calculation of the weight-volume
relationship.
DEFINITION
The specific gravity of a given material is defined as the ratio of the weight of a given
Volume of the material to the weight of an equal volume of distilled water at a stated
temperature.
The general ranges of the values of G, for various soils are given in Table below. The
Procedure for determination of specific gravity, G" described here is applicable for soils
Composed of particles smaller than 4.75 mm (No.4 U.S. sieve) in size.
General ranges of Gs for various soils:
Soil type Range of Gs
Sand 2.63-2.67
Silts 2.65-2.7
Clay and silty clay 2.67-2.9
Organic soil Less than 2
APPARATUS REQUIRED
1. Volumetric flask (pycnometer) of 500 ml with its stopper.
2. Balance to weigh the materials (accuracy 10gm).
3. Wash bottle with distilled water.
4. Thermometer.
OBJECTIVE
Determine the specific gravity of soil fraction passing 4.75 mm I.S sieve by Pycnometer.
NEED AND SCOPE
1-The knowledge of specific gravity is needed in calculation of soil properties like void
ratio, degree of saturation etc.
2-specific gravity of soil is an important parameter for calculation of the weight-volume
relationship.
DEFINITION
The specific gravity of a given material is defined as the ratio of the weight of a given
Volume of the material to the weight of an equal volume of distilled water at a stated
temperature.
The general ranges of the values of G, for various soils are given in Table below. The
Procedure for determination of specific gravity, G" described here is applicable for soils
Composed of particles smaller than 4.75 mm (No.4 U.S. sieve) in size.
General ranges of Gs for various soils:
Soil type Range of Gs
Sand 2.63-2.67
Silts 2.65-2.7
Clay and silty clay 2.67-2.9
Organic soil Less than 2
APPARATUS REQUIRED
1. Volumetric flask (pycnometer) of 500 ml with its stopper.
2. Balance to weigh the materials (accuracy 10gm).
3. Wash bottle with distilled water.
4. Thermometer.
