Sp. Gravity & Water Absorption Of Coarse Aggregate

The object of the experiment is to determine the Specific Gravity & Water Absorption of Coarse Aggregate. Specific Gravity is the ratio of the mass of a unit volume of aggregate at a stated temperature to the mass of the same volume of gas-free distilled water at a stated temperature.

1. Weighing balance
2. Thermostatically controlled oven
3. Glass vessel
4. Enamel tray
5. Airtight container
6. 10 mm IS sieve

1. Sieve the sample through a 10 mm sieve to remove finer particles. Now take sample 1 kg.

2. Place the sample in a glass vessel and fill the vessel partly with water. Keep the sample for 24 hours so that they are completely saturated.

3. After 24 hours fill the vessel completely and cover the vessel with a disc so that no air can be entrapped into a vessel. Dry the vessel from outside. Now take the weight.

4. Drain the water of the vessel. Now aggregates are placed on a dry cloth till it comes in SSD (Surface Saturated Dry) condition. Now weight.

5. Now fill the vessel with water completely. Cover the vessel with a disc so no air can get into it. Now weigh it.

6. Now place the SSD sample in enamel tray and keep it in thermostatically oven at 100-degree Celcius for 24 hours. After 24 hours, let the sample cooled in an airtight container. Now weigh it.

Calculate the Specific Gravity & Water Absorption of Coarse Aggregate using the following formula :

SPECIFIC GRAVITY = D / C – (A – B)

WATER ABSORPTION = [(C – D)/D] x 100