Concrete

 A construction material composed of fine aggregates (sand), cement and coarse aggregates mixed with water which hardens with time is called Concrete. Mostly used type of cement for production of concrete is Portland Concrete. Concrete technology deals with study of concrete properties and its practical applications. Concrete is used for the construction of columns, foundations, beams, slabs and other load bearing elements in a building construction. For road construction, there are different types of binding material are used other than cement such as bitumen for asphalt concrete and lime for lime concrete. Components of concrete are sand, cement, aggregates and water. Mixture of water and Portland cement is called as paste. So, concrete can be called as a mixture of sand, paste and aggregates. Instead of aggregates, sometimes rocks are used. The cement paste coat the surface of the fine and coarse aggregates when mixed thoroughly and binds them. A hydration reaction start which provides strength and a rock solid concrete is obtained soon after mixing the components.