CLASSIFICATION AND CHARACTERISTICS OF BRICK

SHAPE AND SIZES OF BRICK
First class bricks
Second class bricks
Third class bricks
Fourth class bricks
SIZE AND SHAPE
COLOUR
TEXTURE AND COMPACTNESS
HARDNESS AND SOUNDNESS
WATER ABSORBTION
CRUSHING STRENGTH

1. BRICKS One of the oldest building material

2.     Brick continues to be a most popular and leading construction material because of being cheap, durable and easy to handle and work with.

3. Used for This Photo by Unknown author is licensed under CC BY .

4. SHAPE A brick is rectangular in shape and of size that can be conveniently handled with one hand. Length of brick =                   2 × width of brick + thickness of mortar Height of brick = width of brick

5. SIZE Size of a standard brick should be       19 × 9 × 9 cm and 19 × 9 × 4 cm. When placed in masonry the 19 × 9 × 9 cm brick with mortar becomes 20 × 10 × 10 cm. FIELD  :  9”x 4.5” x 3”

6. CLASIFICATION First class bricks Second class bricks Third class bricks Fourth class bricks

7. First class bricks These bricks are well burnt, having smooth and even surface. A metallic or ringing sound should come when two bricks are struck against each other. Water absorption should be 12 -15% of its dry weight when immersed in cold water for 24 hrs Crushing strength should not be less than 10N/mm^2.

8. First class bricks Uses: These are used for outer walls and facing works when no plastering is done. These are also used for floors and reinforced brick works.

9. Second class bricks These are not perfectly rectangular in shape. Has rough surface Hard, slightly over burnt  Uniform in colour Water absorption should be 16 -20% of its dry weight when immersed in cold water for 24 hrs Crushing strength should not be less than         7 N/mm^2

10. Second class bricks Uses: Hidden masonary works Used for facing works when plastering is done Internal walls and partition walls

11. Third class bricks These are under burnt These are soft and light colour Water absorption should not be more than 25% of its dry weight when immersed in cold water for 24 hrs Uses: Temporary structures inferior structures

12. Fourth class bricks These are over burnt Distorted in shape and size Dark in colour Uses: Not used in brick work But used in the form of broken pieces, Used for road ballast

13. CHARACTERISTICS OF GOOD BRICK SIZE AND SHAPE The bricks should have uniform size and plane, rectangular surfaces with parallel sides and sharp straight edges. COLOUR The brick should have a uniform deep red as indicative of uniformity in chemical composition and thoroughness in the burning of the brick.

14. CHARACTERISTICS OF GOOD BRICK TEXTURE AND COMPACTNESS The surfaces should not be too smooth to cause slipping of mortar. The brick should have precompact and uniform texture. A fractured surface should not show fissures, holes grits or lumps of lime.

15. CHARACTERISTICS OF GOOD BRICK HARDNESS AND SOUNDNESS The brick should be so hard that when scratched by a finger nail no impression is made. When two bricks are struck together, a metallic sound should be produced.

16. CHARACTERISTICS OF GOOD BRICK WATER ABSORBTION should not exceed 20 per cent of its dry weight when kept immersed in water for 24 hours. CRUSHING STRENGTH should not be less than 10 N/mm^2