Table of Contents
In this article, we will discuss the Bulkage of Sand.
When there is a rise in the moisture content in the sand, it increases the volume of the sand. This process is known as the Buckling of sand.
1. Bulkage of Sand
The cause for buckling is that moisture present makes the film of water over the surface of sand particles, leading to the rise in the volume of the sand.
If the moisture content is 5 to 8 percent, volume will rise by 20 to 40 percent.
For finer sand = High increase in volume
For coarse sand = Less increase in volume
When the water content in the saturated sand is risen by putting extra water, the sand particles pack around each other, and the quantity of bulking of sand is reduced. Thus it helps in calculating the actual volume of sand.
The volumetric proportioning of sand is highly affected by bulking of sand to a greater extent. The affected volume will be huge for fine sand and low for coarse sand.
If the needed allowance is not made for the bulking of sand, the cost of concrete and mortar will rise, resulting in under-sanded mixes, which affect workability.
2. Objective
To find the bulkage of sand.
3. Apparatus Required
The following apparatus are required for determining the bulkage of sand:
a. Measuring Cylinder
b. Container
c. Steel Rule
d. Steel Rod (6mm Dia)
e. Sample sand
4. Procedure
To determine the percentage of bulking of sand, the following steps
are carried out.
1. A standard container is used, and it is filled with (2/3)rd of the sand to be tested.
2. The height of sand in a container is measured (H), for example, 200 mm.
3. Now, the sand is removed from the container. More care should be taken to see that no remains of sand should be there in the container during this migration.
4. The identical container is filled with water, say 100ml.
5. Put the sand into the container filled with water and slightly move to the sand with a rod.
6. Again, a container’s height of fully saturated sand (Y) is measured, say 160 mm.
Bulking of sand is determined through this calculation, = (200-160)/160 = 40/160 = 1/4 (or) 25%.
5. Calculation
Bulking of Sand= { (H-Y)/Y } x 100%
Where,
The height of Unsaturated Sand in a container = H
The height of fully Saturated Sand in a container = Y
6. Observation Sheet
So the sand bulkage for this observation result = (33.3+29.87+27.38)/3 =30.19%
Read More: Density Test of Sand
