A short presentation on BRICK & its characteristic,types, manufacturing process,composition of bricks,quality of good bricks,classification on class & shape of bricks, testing etc.

1. BRICK
BRICK

2. GENERAL INTRODUCTION
 Brick is one of the oldest building material.
 It is extensively used at present as a leading
material of construction because of its durability,
strength,low cost, easily available etc.
The bricks are obtained by moulding clay in
rectangular block of uniform size and then by drying
and burning these blocks.

3. COMPOSITION OF GOOD
BRICK
 ALUMINA : a good brick should contain about 20%
to 30% of alumina. This constituent imparts plasticity
to the earth so it can be moulded.
 SILICA : a good brick contain 50% to 60% of silica.
The presence of this constituent prevent cracking,
shrinking and warping of bricks.
 LIME : a small quantity of lime not exceeding 5% is
desirable in good brick. It should be present in very
finely powered state because even small particles of
the size of a pin head cause flaking of the brick.

4.  OXIDE OF IRON : a good brick contains about
5% to 6% of oxide of iron. It imparts red colour
to the bricks.
 MAGNESIA : a small quantity of magnesia in brick
imparts yellow tint to the bricks and decreases
shrinkage.

5. HARMFUL INGREDIENTS
IN BRICK
 ALKALIES : the alkalies act as a flux in the kiln
during burning and they cause bricks to fuse ,twist
and warp. As a result bricks are melted and they
loose their shape
 PEBBLES : the presence of pebbles or grits of any
kind is undesirable in brick because it will not allow
the clay to mixed uniformly and which will result in
weak brick.
 VEGETATION AND ORGANIC MATTER :
presence of this matter in brick assist in burning .
But if such matter is not completely burnt,the brick
become porous.

6. TYPES OF BRICK
 Sun dried brick /unbaked
Burnt brick/ baked
Sun dried brick : these bricks are dried with help of
heat receives from sun after the process of moulding.
These bricks can only be used in the construction of
temporary and cheap structures. Such bricks should
not be used at places exposed to heavy rains.
Burnt brick : these brick are dried with the help of
kiln.

7. MANUFACTURING OF
BRICKS
 PREPARATION OF CLAY : clay for brick is
prepared in following orders:
I. Unsoiling
II. Digging
III. Cleaning
IV. Weathering
V. Blending
VI. Tempering
 MOULDING
 DRYING
 BURNING

9. CLASSIFICATION OF BRICK
On the basis of manufacturing
 FIRST CLASS BRICK : the surface and edges of
the bricks are sharp,smooth and straight. This brick
are used for superior work.
 SECOND CLASS BRICK: surface of this brick is
somewhat rough and shape is also slightly irregular.
This brick is used at place where brickwork is to be
provided with a coat of plaster.
 THIRD CLASS BRICK: this brick is not hard and
they have rough surfaces with irregular edges. They
are used for unimportant and temprory structure.

10.  FOURTH CLASS BRICKS : these are overburnt
brick which are irregular shape and dark colour. This
brick is used as aggregate for concrete in
foundation,floors,roods etc.

11. ON THE BASIS OF SHAPE
 Half bat
 Three quarter bat
 Queen closer
 King closer

12. ON BASIS OF SIZE
 Traditional brick
 Modular brick.

13. USES OF BRICKS
 First and second class bricks are widely used for all
sorts of sound work especially of permanent nature.
These structure include buildings,dams,sewers,bridge
piers, etc
 The use of first class is specified effects on face of
structure where they are to be kept exposed for
beauty
 The third class and sun dried bricks are used for
construction work of temporary nature.

14. TESTS FOR BRICKS
 ABSORPTION : a brick is dry weight then
immersed in water for16 hours, weight again the
difference in weight indicates the ammount
absorbed by the brick. It should not exceed 20%
weight of dry brick.
 HARDNESS OF BRICK : a scratch is made on
brick surface with the help of a figure nail. If no
impression is left on the surface then the brick is
treated to be sufficient hard
 SOUNDNESS: two brick are taken and they are
struck with each other. The brick should not break
and a clear ringing sound should be produce.

17. QUALITIES OF GOOD BRICK
 The brick should be well burnt, coppered coloured,
free from cracks, and with sharp edges.
 the brick should be uniform in shape and should be
standard size.
 The brick should give a clear metallic sound when
struck with each other.
 The brick should not break into two pieces when
dropped on ground from a height of about 1 M.