Brick is a material that is formed by the composition of silica, alumina, iron oxide, etc. If they are used in more quantity than required, it will act as a harmful ingredient. For strong, sound and durable brick; it should be free from different harmful materials and ingredients like lime, organic matter, etc. Some harmful ingredients in brick earth with their effects are:
Harmful ingredients in brick earth
A small amount of lime is used in brick but excessive use of line leads to brick melting disintegrates the bricks. Bricks also lose their shape due to the excessive use of lime.
Although lime is one of the binding material; more than 1 % of lime in brick leads to problems.
2) Organic Matter:
It makes the brick dark and porous in nature. Almost all the organic matters present in brick are burnt down during the burning process of brick. If completely not burn then it will lead to problems like porous, darkness, etc.
The use of more than 1% of organic matter in brick leads to problems.
3) Sulphides and Sulphates:
Sulphides and sulphates affect the bricks like lime. The improper shape of bricks may be due to the presence of sulphates and sulphides.
It causes crystallization and disintegration during the burning of brick, so it split the brick into pieces.
It acts as a soft during burning and crates addition softening which causes twisting and warping.
Alkalies also may lead to efflorescence ( appearance of white color powder on brick surface ). Efflorescence leads to de-coloration, unhygienic condition, disintegration of masonry, etc
5) Pebbles of stone and gravel:
The presence of pebbles in brick leads to non-uniform mixing of clay which may lead to non-uniform shape and also make brick porous.
Brick containing pebbles may break down into pieces when a very small amount of load is subjected. The figure of such failure is given below.
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