Different classifications of bricks before brickwork.

Types of bricks

Bricks: Bricks are one of the most important building material used in masonry construction.They are mainly rectangular in shape.

In earlier time,bricks are mostly manufactured from clay. But from many years bricks are constructed from other materials also as per their use,strength,durability etc.

CLASSIFICATION OF BRICKS:

Bricks are classified as follows:

1.  Classification of bricks based on process of manufacture:

  a) UN Burnt bricks: These bricks are dried in sun not in kiln at high temperature and used                                           in temporary constructions.

Sun dried brick

  b)  Burnt bricks:  These bricks are mainly used for masonry constructions.bricks are burnt                               in kiln at high temperature  to provide adequate strength,durability to bricks.

Burnt brick

 These are further classified in four classes:

 First class bricks:

 1.These bricks are intensively burnt and are of deep red, cherry or copper color.
 2.The surface of bricks should be smooth and rectangular, with parallel, sharp and straight       edges and square corners.
 3.These bricks should be free from flaws, cracks and stones.
 4.These bricks should have uniform appearance.
 5.No impression should be left on the brick when a scratch is made by a finger nail.
 6.The fractured surface of the brick should not show lumps of lime.
 7.A metallic or ringing sound should come when two bricks are struck against each other.
 8.Water absorption should be 12-15% of its dry weight when immersed in cold water for 24         hours. 
 9.The crushing strength of the brick should not be less than 10 N/mm 2.

 Second class bricks:

 1.Small cracks and distortions are permitted.
 2.A little higher water absorption of about 16-20% of its dry weight is allowed.
 3.The crushing strength should not be less than 7.0 N/mm 2.

Third Class Bricks:

Third Class Bricks are under  burnt. They are soft and light colored producing a dull sound when struck against each other. Water absorption is about 25 per cent of 

 dry weight.

Fourth Class Bricks:

Fourth Class Bricks are over burnt and badly distorted in shape and size and are brittle in nature.

2. Classification of bricks on the basis of material used:

     Clay brick: Brick formed of clay extruded into the required shape in the manufacturing plant.

   Sand-lime brick:Sand-lime brick is a product that uses lime instead of cement. It is usually                                 a  white brick made of lime and selected sands, cast in molds and cured

     Concrete bricks:Concrete brick is a mixture of cement and aggregate, usually sand,                                               formed in  molds and cured.

     Fly ash bricks:  Bricks which are formed of fly ash(by product of thermal power plant) .

More important information about bricks are below:

Various properties of bricks
Different field test of brick on construction site