Characteristics and Classification of Bricks
Various types of bricks are found in the market which can be used in building construction. The bricks are classified on the basis of manufacturing process that range from Unburnt or sun-dried bricks and Burnt bricks. Given below the detailed lists of various types of bricks :-
Unburnt bricks: Unburnt bricks or sun-dried bricks belong to the types which are dehydrated through heat generated by the sun once the process of moulding is completed. These types of bricks are utilized for building the temporary and low-priced structures. It is recommended that these types of bricks are unfit for the areas uncovered to deep rainfall.
Burnt Bricks: Burnt bricks are formed after blazing the brick-mould in the drying oven within the factory. These types of bricks are generally utilized for construction processes. Burnt Bricks are segregated into the following four categories:
First class bricks: These bricks belong to table-moulded and contain customary shape. The bricks are parched in drying oven. The facades and edges of the bricks are sharp, square, flat and straight. These bricks maintain superior quality. The bricks are crack free. The brick contains least crushing strength of 7 N/mm2. This is used for the construction of superior work i.e. heavy foundation and structures.
Second class brick: These bricks belong to ground-moulded and they are burnt in kilns. The facade of these bricks is uneven to some extent and shape is also somewhat unequal. These bricks may contain fine hair cracks and little distortion. The edgings of these bricks are sharp and homogeneous. These bricks are generally applied in the areas where brickwork is supported with a coat of plaster. The minimum crushing strength of second class brick should be 70 kg per sq cm
Third class bricks: These bricks belong to ground-moulded and are moulded in drying ovens. These bricks are not so hard and include rough surfaces with uneven and distorted edges. These bricks provide dull sound if set collectively. The bricks are useful for minor and temporary structures and at areas where rainfall is normal. The bricks are formed with light color and are comparatively soft.
Fourth class bricks: These types of bricks are also known as over-burnt bricks which contain uneven shape and dark black or grey color. These bricks are used as aggregate for concrete in foundations, floors, roads, etc. owing to the over-burnt bricks consist of a solid structure and so they are strong enough as compared to the first class bricks. These types of bricks are generally used in substandard construction and as gravel for flooring. The bricks contain bulging surfaces. The compressive strength of this brick is very low.
The categorization can also be made on the basis of shapes to fit them for specific type of construction. Go through the following link to know various types of bricks available in diverse shapes.