bulkage of sand

Bulkage of Sand | Lab Experiment

 

In this article, we will discuss the bulkage of sand and test carried out to determine the bulkage of sand.

 

  1. Introduction  

When there is a rise in the moisture content in the sand, it increases the volume of the sand. This process is known as Buckling of sand.

The cause for buckling is that moisture present makes the film of water over the surface of sand particles that lead to the rise in the volume of the sand.

If the moisture content is 5 to 8 percent, then there will be a rise in volume by 20 to 40 percent.

For finer sand = High increase in volume

For coarse sand = Less increase in volume

Bulkage of Sand

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 real volume of sand.

The volumetric proportioning of sand is highly affected by bulking of sand to a higher extent. The affected volume will be huge for fine sand and will be low for coarse sand.

If the needed allowance is not done for the bulking of sand, the cost of concrete and mortar will rise, and also results in under-sanded mixes which affect workability.

 

  2. Objective  

To find the bulkage of sand.

 

  3. Apparatus Required  

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 normal 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, say 200 mm.

3. Now, the sand is removed from the container. More care should be done to see that no remains of sand should be there in the container during this migration.

4. Now the same or identical container is filled with water, say 100ml.

5. Put the sand into the container filled with water and do a slight movement to the sand with a rod.

6. Again, the height of fully saturated sand (Y) in a container is measured, say 160 mm.

Bulking of sand is determine through this calculation, = (200-160)/160 = 40/160 = 1/4 (or) 25%.

Bulkage of Sand

 

 

  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   

 

Bulkage of sand

So the sand bulkage for this observation result = (33.3+29.87+27.38)/3 =30.19%

 

Read More: Density Test of Sand

 

Read More:  Types of Sand