What is bulking of sand?
Bulking of sand means increase in it’s volume due to presence of surface moisture . The volume increases with increase in moisture content . The volume may increase up to 20 to 40% when moisture content is 5 to 10 %.
As fine grained sands have higher voids than medium and coarse grained sands, the percentage of moisture absorbed and the percentage volume increase is the highest.
When water is added to sand, a thin film of water is formed around the sand particles. The film exerts surface tension on particles, making them move apart. This leads to increase in volume because there is no direct contact among particles.
AIM
The bulking of sand test should do as per IS 2386.
Apparatus
- Measuring Cylinder
- Container
- Steel Rule
- Steel Rod (6mm Dia)
- Sample sand
Procedure
- Take a 250 ml capacity of measuring cylinder.
- Fill the sand up to 200 ml and shake well then record the level as a.
- Add 100 ml water to the cylinder to saturate the sand completely and stir well.
- Now add the measured sand to the container and wait for some time to settle down.
- The sand will be below the 200 ml mark. Note this level as b
- Repeat the same procedure for 2 more samples
Calculation
bulking of sand = {(200-b)/b} x 100
Observation Table
| S.No | DESCRIPTION | SAMPLE NO. | ||
| SAMPLE I | SAMPLE II | SAMPLE III | ||
| 1 | Volume of Loose Sand | |||
| 2 | Volume of Saturated Sand | |||
| Bulking of Sand= {(200-b)/b}x100 % | ||||
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