Materials Used in Construction
Construction of home, bridges, roads and dams use natural stone wood, metals and bricks, lime, cement, concrete, etc. Natural stones like granite, marble and sand stone are also used. These materials have been used in the construction of nagarjun sagar dam.
Tajmahal, vridheshwar temple and Lal Qila of Delhi, Indian sculpture is world famous for its monumental heritage on stone and building vast temples, we have seen making big temples by joining pieces of stone without mortar in earlier times. These stones are used now a days in homes and buildings in cities.
Construction sites also use brick prepared by baking loamy soil. Earlier it was used to join stones and bricks. Afterwards bitumen and lime began to be used. However, Portland cement was invented in the 19th century. Now cement is used in constructing homes, buildings, bridges, etc.
Portland cement was discovered by Joseph Espidy in 1824. He mixed limestone and loamy soil to make a powerful water resistant material. The colour of this material looked like the lime stone of Portland. Therefore, the material was called Portland cement.
Modern Portland cement has 60-70% calcium oxide, 17-25% silica, 3-8% aluminum oxide and up to 6% iron oxide. Lime stone and loamy soil is mixed as per desired ratio. This is heated in a rotary kiln at the temperature of 1150 Kelvin. The material is called clinker. When powdered gypsum is mixed with this material, cement is produced.
The plastering material is prepared by mixing sand, cement and water to hold brick and stones. It is also used for plastering.
Concrete is formed by mixing sand, soil and water in cement. This is used in corners of road and middle pathways, roofs of homes and electricity poles.