2. CONTENT
What is Brick ?
Composition Of good Brick Earth.
Types of Brick .
Manufacturing of Brick.
Harmful ingredient in Brick.
Quality of good Brick.
Tests on Brick.
Size , Weight and colour of Brick.
Uses of Brick.
Application of Brick.
Reference.
3. WHAT IS BRICK ?
A brick is a building material used to
make walls , pavements and other
elements in masonary constructions. Fig.: Brick
4. COMPOSITION OF GOOD BRICK EARTH
ALUMINA (20-30%)
SILICA ( 50-60%)
LIME (5%)
OXIDES OF IRON (5-6%)
MAGANESIA (1%)
6. First Class Bricks .:
These Bricks are well burnt , having smooth & even surface, with
perfect rectangular shape& uniform reddish colour. When you stuck
each other , these give a metallic ringing sound. These should not
absorb water more than 20% of its weight when immersed in cold
water for 24 hrs.
Crushing Strength less than in 55 kg/cm2 is not allowed.
Minimum Compressive strength is 35 kg/cm2.
Use .:
They are used as good structure as outer walls and facing works
when no plastering is done. These are also used in floors and
reinforced bricks slab. Such bricks should be laid in rich mortar.
7. Second Class Brick .:
They are not perfectly rectangular in shape and are having rough
surface, but are hard, slightly over burnt and uniform in colour.
These give ringing sound when struck with each other. Water
absorption is more than 22% by weight, when immersed in water for
24 hrs.
Use .:
These are used for internal walls , not exposed to atmosphere ,
these are used in facing work, which should be plastered. These can
not be used for R. B. Work . Such bricks may be laid in mud or lime
mortar.
8. Third Class Bricks .:
These bricks are also known as “Pila Bricks”. These are not burnt
properly in the kilns & may be slightly under burnt, hence these are
soft & can be easily broken. These are light red in colour , with
yellowish tinge. On striking , these do not give a ringing sound.
These should not absorb more than 25% of water by weight when
placed in cold water for 24 hrs.
Use .:
These are used for inferior construction works, or at place when
there is less rain fall or presence of dampness.
9. Fourth Class Bricks .:
It is also known as “Jhama and Over Burnt Bricks ”. Due to excess
fusion & temperature bricks are over burnt, loose their shape &
get twisted. These bricks are dark bluish in colour.
Use .:
These bricks are not used in brick work. They are used in the form
of broken pieces, these may be used as road metal, also in
foundation and floors as soling material.
17. HARMFUL INGRADIENT IN BRICKS
LIME :- It causes unsoundness in bricks if present in excess
amount.
IRON PYRITES :- If iron pyrites are present in bricks earth
bricks get crystallized and disintegrated during burning.
Alkalies :- The alkalies set as a flux in the kiln during burning
and they cause bricks to fuse, twist and wrap.
PEBBLES :- They will not allow the clay to get mixed
uniformly which will results In weak and porous bricks.
ORGANIC MATTER :- If they do not burn completely, bricks
becomes porous.
18. QUALITY OF GOOD BRICKS
The bricks should be table moulded will burnt in kilns, free from cracks and with
square edges. The colour should be uniform and bright
The brick should give a clear ringing sound when struck with each other.
The brick when broken or factured should not show a bright homogeneous and
uniform compact structure free from voids .
The brick should be sufficiently hard. No impression should left on brick surface
when it is scratched with finger nail.
The brick should not break into pieces when dropped flat on hard ground for a
height about one meter.
The brick, when soaked in water for 24 hours should not show deposits of white salt
when allowed to dry in shade.
The brick should not absorb water more than 20 % by weight for first class brick and
22% by weight for second class brick when soak in cold water for 24 hours.
No brick should have crushing strength below 5.50N/mm sqr.
19. TESTS ON BRICKS
Absorption
Crushing Strength
Hardness
Presence of soluble salts
shape and size
Soundness
Structure
20. (1). Absorption Test
Take a brick weighed dry.
Immerse in water for 16 hours.
Again weight and difference in
weight indicates amount of water
absorb by brick.
It should not exceed 20% of
weigh to dry brick.
Fig.: Water Absorption
21. (2). Crushing Strength Test
It should found out by placing brick in
compression testing machine.
It is pressed till it breaks as per IS:1077-1970
The minimum compressive strength of brick
is 3.50N/mm sqr.
The brick crushing strength is 7 to 14 N/mm
sqr. Are graded A . And those having above 14
N/mm sqr. are graded AA .
Fig.: Test on CTM
22. (3). Hardness Test
A scratch is made on brick surface
with the help of finger nail.
If no impression is left on the
surface the brick is treated to be
sufficiently hard.
23. (4). Shape and Size Test
In this brick should be of standard size and
its shape should be truly rectangular with
sharp edges.
for this 20 bricks of standard size ( 190 mm
* 90 mm * 90 mm ) are selected at random.
they are stacked length wise along the
width and along the height .
The result should be ..
Length = 3680 mm to 3920 mm
Width = 1740 mm to 1860 mm
Height = 1740 mm to 1860 mm
24. (5). Soundness Test
Take two bricks and struck with each
other.
The brick should not break and give clean
ringing sound should be produced.
25. (6). Structure Test
A brick should be homogeneous
compact and free from any defects
such as holes lumps etc.
26. SIZES AND WEIGHT OF BRICKS
Standard size of bricks is 19cm*9cm*9cm.
Nominal size with mortar is
20cm*10cm*10cm.
Commonly adopted nominal size of
traditional brick is 23cm*11.4cm*7.6cm.
It is found that the weight of 1 cubic meter of
brick earth is about 1800 kg hence the average
weight of a brick is about 3 to 3.50 kg.
27. USES OF BRICKS
As building blocks.
For lining of ovens, furnance and
chimneys.
For protecting steel column from fire.
As aggegrate in providing water proofing
to RCC roof.
For pavers for footpaths and cycle
tracks.
For lining of sewers line.
28. The world’s highest brick tower of St.
Martin’s Church in Landshut, Germany,
completed in 1500.
The ancient Jetavanaramaya stupa in
Anuradhapura, Sri Lanka is one of the
largest brick Structures in the world.
APPLICATION OF BRICK
Fig.: St. Martin Church
Fig.: Jetavanaramaya Stupa
29. REFERENCE
Engineering Material Book
written by .: “ Late S.C. Rangwala ”
Building Material and construction book
Written by .: “Dr. Sanjeev Singh ”
Pictures are from “Google”
