BRICKS
BRICKS
Bricks are one of the oldest known building materials dating back to 7000BC where they were first found in southern Turkey and around Jericho. The first bricks were sun dried mud bricks. Fired bricks were found to be more resistant to harsher weather conditions, which made them a much more reliable brick for use in permanent buildings, where mud bricks would not have been sufficient.
Bricks nowBricks are more commonly used in the construction of buildings than any other material except wood. Brick and terracotta architecture is dominant within its field and a great industry has developed and invested in the manufacture of many different types of bricks of all shapes and colours. With modern machinery, earth moving equipment, powerful electric motors and modern tunnel kilns, making bricks has become much more productive and efficient. Bricks can be made from variety of materials the most common being clay but also calcium silicate and concrete. With clay bricks being the more popular, they are now manufactured using three processes soft mud, dry press and extruded. Also during 2007 the new fly ash brick was created using the by-products from coal power plants.
How bricks are made?Bricks are made from wetting clay which you press it into a mould and then bake the clay in an oven until it is hard.The traditional wayRaw Materials
Natural clay minerals, including kaolin and shale, make up the main body of brick. Small amounts of manganese,barium, and other additives are blended with the clay to produce different shades, and bariumcarbonateis used to improve brick's chemical resistance to the elements. Many other additives have been used in brick.
A wide variety of coating materials and methods are used to produce brick of a certain color or surface texture. Sometimesa fluxorfrit(a glass containing colorants) is added to produce surface textures..Other materials including graded fired and unfired brick, nepheline syenite, and graded aggregate can be used as well.
The ManufacturingProcess1-Grinding, sizing, and combiningraw materials2-Extrusion3-Coating4-Drying5-firing
Brick format The format of brick is 90mm x 90mm x 90mm and 190mm x190mm x 190mm .
With mortar joints ,the size of these bricks are taken as 200mm x 100mm x 100mm and 200 mm x 100 mm x 50 mm .
The most common brick size is the Imperial Brick, which measures 222mm long x 106mm wide x 73mm high with a mass of between 3.0kg.
There are also other sizes and formats available.
Types of bricksConcrete BricksThese bricks have either pale green or gray color. These are prepared from a small, dry aggregate concrete which is formed in steel molds by using vibration and compaction. The entire manufacturing process is incurred either in an egg Layer or static machine. Rather than firing, the curing process is used to convert the blocks thus prepared into bricks under low pressure steam.
High Alumina BricksHigh alumina bricks from 50% upto 90% Alumina are made with various selected superior grade aggregates to meet the various service conditions of various types of furnaces like laddie, blast furnace, cement and sponge iron Rotary Kiln, calciner , etc., The 90% alumina dense bricks are manufactured from tabular alumina purer micro fine alumina and other special type raw material and fired in ultra high temperature kiln at 1650-1700BC. Due to the intent micro structural features of the raw materials used for these bricks, they have excellent resistance to wear and thermal shock.
Fire BrickA fire brick is a block of ceramic material used in masonry construction and sized to be layed with one hand using mortar. Bricks may be made from type of material .These are built primarily to withstand high heat and also find applications in extreme mechanical, chemical, or thermal stresses. The brick is widely used as refractory insulating bricks for maintaining insistent temperature.Light Weight Hollow BlocksThis blocks are used in construction of houses in earthquake prone areas. These bricks are made of fly ash, cement, lime, gypsum, stone dust etc. Available in different sizes. Hollow concrete blocks is used as substitute for conventional bricks or stones used in construction of buildings. And the blocks' importmant feature
Properties of bricksAesthetic Bricks offer natural and a variety of colors, including various texturesStrength Bricks offer excellent highcompressive strength.Porosity The porosity of bricks in attributed to its fine capillaries. The ability to release and absorb moisture is one of the most important and useful properties of bricks, regulating temperatures and humidity inside structures. Fire Resistance When prepared properly a brick structure can give afire protection maximum rating of 6 hours
Sound Insulation The brick sound insulation is normally45 decibels for a 4.5 inches brick thickness and 50 decibels for a nine inch thick brick.Insulation Bricks can exhibitabove normalthermal insulation when compared to other building materials. Bricks can help regulate and maintain constant interior temperatures of a structure due to their ability to absorb and slowly release heat. This way bricks can produce significant energy savings, more than 30% of energy saving, when compared to wood.Wear A brick is so strong, that its molecular composition provides excellent wear resistance.Efflorescence Efflorescence forms on concrete structures and surfaces when soluble salts dissolved in water are deposited and accumulated on surfaces forming a visible scum.
Classification The bricks used in construction are classified as:First class bricksSecond class bricksThird class bricksFourth class bricksTests on bricksCrushing strength testWater Absorption testEfflorescence testHardness testSize, Shape and Color testSoundness testStructure test
USESStructuraluses: such asfoundationswalls and floors.Decorative/ornamental uses: May be cast to from moldings and otherdecorativefeatures may be carvedalso may be used in avarietyofcolors, textures, bondsandjoints.May beconcealedby otherfinish materialssuch asstucco, plasterorpaint,or may be exposed bothon theinteriorandexterior.Bricksare also used in themetallurgyand glassindustriesforlining furnaces.They have various uses, especially refractorybrickssuch assilica, magnesia, chamotteandneutral(chromomagnesite)refractory bricks.Thistypeofbrickmust havegood thermal shock resistance, under load,high melting point, andsatisfactory porosity.Bricksare used forbuildingandpavement.Earlier brickpavement was found incapable of withstandingheavytraffic,butit is coming back into use as amethodoftraffic calmingor as adecorative surfaceinpedestrian precincts.
AdvantagesThe use ofmaterialssuch asbrickand stone can increase the thermal mass of building, giving increased comfort in the heat of summer andcoldofwinterand can be ideal forpassive solar applications.Brick typicallywill not require painting and so canprovidea structure with reduced life cycle costs, although sealing appropriately will reduce potentialspallingdue to frostdamage. Concrete blockof the non decorativevarietygenerally ispaintedorstuccoedif exposed.Theappearanceespecially when wellcrafted,can impart an impression of solidity and permanence.Brickis very heatresistant materialand thus will provide good fireprotection.Being much more resistant tocoldandmoistweatherconditions, brick enabledthe construction ofpermanent buildingsin regions where the harsherclimate precludedthe use of mud bricks.
