How to check Quality of brick at construction site

Bricks are small rectangular blocks that can be used to form parts of buildings, typically their walls. Bricks are most typically made from clay, although they are also commonly made from calcium-silicate and concrete.

Type of bricks

• Sand lime bricks
• Fly ash clay bricks
• Burnt clay bricks
• Engineering bricks

For good quality of structure, good quality materials are required. In this blog i will tell you some simple yet effective brick tests you can take to check the quality of bricks

Type of test on brick for construction

1. Water Absorption
2. Visual inspection
3. Dimension
4. Efflorescence
5. Hardness
6. Soundness
7. Structure 
8. Crushing Strength 
9. Impact Test

1. Absorption Test

Absorption test is done to find out the amount of moisture content absorbed by brick under extreme conditions. In this test 5 bricks are taken and the bricks are weighed dry and the average dry weight of 5 bricks is calculated.

Then immersed in clean water at a temperature of 27+2°C for 24 hours. . After 24 hours of immersion, bricks are weighed again and average of 5 bricks is calculated. The difference of the final average weight and initial average weight indicates the amount of water absorbed by the bricks. It should not in any case exceed 20%  of average weight of dry bricks.

Calculation

Visual inspection

In this test of bricks are closely inspected for its shape , colour and dimension. The bricks of good quality should be uniform in shape and have rectangular shape with sharp edges.
Standard brick size consists length x breadth x height as 190 mm x 90 mm x 90 mm

Dimension

Take 15 – 20 brick make  stack them along its length , breadth and height and compare. So, if all bricks similar size then they are qualified for construction work. tolerance in it ±3 mm for class one and ± 5 mm for other classes.

Efflorescence

A good quality brick should not contain any soluble salts in it. If soluble salts are there, then it will cause efflorescence on brick surfaces.

This test should be conducted in a well ventilated room.Place a brick in water bath for 24 hours and dry in shade. If there are white/grey deposits on the surface then the quality of the brick is low as it contains soluble salts.

Hardness

This test is done to know the hardness of bricks. A good brick should resist scratches against sharp things. So, for this test a sharp tool or finger nail is used to make scratch on brick. If it does not leave any impression on the brick surface then it will be considered as good quality bricks.

Soundness

In this test , two bricks are chosen randomly and struck with one another. Then sound produced should be clear metallic sound  and brick should not break. Then these are good quality bricks.

Structure 

In this test, pick one brick from the group and break it. Observe the inner portion of brick clearly. It should be free from any flaws, holes or cracks 

Crushing Strength 

In this test we place the brick in compression testing machine. After placing the brick in compression testing machine, apply load on it until brick breaks same like cube Testing process

Minimum crushing strength of brick is 3.50 N/mm².if it is less than 3.50 N/mm², then it is not good brick

Impact Test

In this test we bricks are dropped the brick from 1.2 to 1.5 -meter height. If bricks are broken it indicates low impact value and not acceptable for construction work.