A brick is building material used to make walls, pavements and other elements in masonry
construction. Traditionally, the term brick referred to a unit composed of clay, but it is now used
to denote any rectangular units laid in mortar. A brick can be composed of clay-bearing soil,
sand, and lime, or concrete materials. Bricks are produced in numerous classes, types, materials,
and sizes which vary with region and time period, and are produced in bulk quantities.
Constituents of good brick earth:
Bricks are the most commonly used construction material. Bricks are prepared by moulding clay
in rectangular blocks of uniform size and then drying and burning these blocks. In order to get a
good quality brick, the brick earth should contain the following constituents.
o Brick earth should contain about 50 to 60 % of silica.
o It is responsible for preventing cracking, shrinking and warping of raw bricks.
o It also affects the durability of bricks.
o If present in excess, then it destroys the cohesion between particles and the brick becomes
o Good brick earth should contain about 20% to 30% of alumina.
o It is responsible for plasticity characteristic of earth, which is important in moulding operation.
o If present in excess, then the raw brick shrink and warp during drying.
o The percentage of lime should be in the range of 5% to 10% in a good brick earth.