Bricks- civil engineering material

Bricks are the civil engineering materials used worldwide, you might have used them while you constructed your home. As you know building stones are not available everywhere so there is always a need for the material which can be used in the masonry work in place of stone. Bricks are manufactured using easily available raw materials like clay, silica, lime iron oxide etc.  You have to control the constituents like lime because excess of lime can result in poor bricks. You should avoid the impurities like pebbles, organic matter and iron pyrite. Various major steps you have to go through are:
(1)collecting raw material
(2)preparation of brick earth and moulding.
(3)Burning the bricks and cooling.
In the first step you have to dig the top surface up to a depth of 20cm to avoid any organic impurities and then take out any other impurities present.
Second step you can complete by two methods Hand moulding and machine moulding. Machine moulding is done using machine.  Afterwards the bricks are dried to gain a certain strength to make them ready for kiln burning.
There are two famous kilns available for burning:
(1)Bull's trench kiln
(2)Hoffman's kiln
A good brick is reddish in color, produces ringing sound when striking with another brick.  Remember it has a water absorption value less than 20%. You should make sure that you get the Indian standard(modular) size brick 19*9*9 cm3 or 19*9*4 cm3.
Burned bricks are classified as 1st class, 2nd class and 3rd class bricks.
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