Besides the Ordinary Portland Cement (OPC), a number of other types of cement are also manufactured by varying the ratio of the raw materials or by adding some additional materials. In addition to ordinary cement, the following are the other important varieties of cement available in the market. Quick setting cement Rapid hardening cement High Alumina cement Blast furnace cement Low heat cement White cement Coloured cement Sulphate cement Expanding cement Pozzolana cement Hydrophobic cement Water proofing cement Acid resistant cement Properties of Quick Setting Cement It contains very little or no retarding substances like gypsum. It is produced by adding a small percentage of aluminium sulphate and by finally grinding the cement. The setting action of the cement starts within 5 minutes after addition of water and cement becomes hard in less than 30 minutes. This type of cement can be used for construction underwater. Properties Rapid Hardening Cement It Also known as High Early Strength Cement. It is manufactured with such adjustments in proportions of raw materials so that the cement produced gains maximum strength within 2 - 4 days. It is used only when time is the most important factor in a project and is used for making very high early strength concrete.
