For the preparation of the concrete patch, a kiln is required in which a mixture of the limestone and clay is burnt on the high temperature. An OPC which is also known as the Portland Cement is produced by grinding the clinker that is formed along with the gypsum in fine pieces. In the Portland cement, a balanced form of the chemicals as such calcium silicates, aluminates, and aluminoferrite is used. And if along with gypsum, Pozzolans is mixed then it is called the Blended. When this Portland cement is mixed with sand, water, and stone in such a way that there is a hard mass formed which ultimately is called the concrete.