Brick Building material Notes for IES and SSC JE - sscwale

Brick Building material Notes for IES and SSC JE - sscwale


Composition of Bricks-

Lime 4-5 %
Silica 50-60%
Alumina 20-30%
Oxide of Iron 5-6%
Magnesia <1%

Manufacturing of Bricks

1- Lime-

It prevent shrinkage of the bricks, it it is in excess it causes the bricks to melt hence results in their lost shape. During burning process lumps of the lime are converted into quick lime that undergoes slaking in the presence of the moisture resulting in the increased volume thereby leading to the cracking or splitting of the bricks.

2- Silica-

It prevent cracking, shrinkage and warping of the bricks, thus impart uniform shape and size to the bricks. If it is in excess, it destroyes the cohesion between the particles due to which bricks become brittle.

3- Alumina-

It imparts plasticity to the brick earth, in so that it can be easily moulded into required shape and size. It it is in excess it causes shrinkage and warping during drying and bricks becomes too hard when it is burnt and break easily.

4- Oxides of iron-

It helps in fusing of lime and silica with each other, moreover it also imparts reddish brown tinge to the bricks.

5- Magnesium oxide-

It imparts yellow tinge to the bricks and avoids the shrinkage in bricks. If it is in excess it leads to decay of bricks.

Harmful ingredients of brick earth-

1- Lime- Due to lime slaking takes place.

2- Iron pyrite- Presence of iron pyrite in brick earth leads to disintegration and crystallization of the bricks during its burning process, due to oxidation of iron pyrite.

3- Alkalies- These are generally present in the form of soda or pottash. They act as a flux during the burning process and causes the fusing of the bricks with each other. It also leads to efflorescence and staining in the structure in which it is used for the construction.

4- Organic matter and vegetative matter- Presence of organic and vegetative matters helps in the burning of the bricks but if those are left unburnt they undergo decomposition over the period of time resulting in the formation of the gases which when escape through the brick make it porous.

5- Stones and pabbles- Presence of stone and pabbles makes the brick porous and reduces its load carrying capacity as it decreases the net availability of area to transfer the load.

Cement Chapter-

Download Cement Chapter PDF NowClick Here

Contact info- iesguruji@gmail.com