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Abstract
The name Portland cement is given originally due to the resemblance of set cement to Portland stone (England). In its broadest since, the word cement denotes any kind of binding agent. This definition includes a wide variety of substances having little in common with one another but their adhesiveness. However, materials most commonly associated with this word arc hydraulic cement of which Portland cement is the most familiar. Ilydraulic cement when mixed with enough water to form a plastic mass (paste), the mixture starts to set, loses its plasticity and becomes hard. The paste continues to harden and properties of the hardened concrete such as strength, volume stability and permeability to water, are mainly determined by the properties of the hydration products in cement paste.Portland cement is manufactured by intimately mixing a calcareous (rich in lime, like limestone) and an argillaceous (rich in silica and alumina such as clay) materials which can be done either in water or in dry condition. i.e. using ”Wet” or ”Dry” proccesses. Mixed and ground raw mixture is burned in a rotary kiln at a temperature up to 1450 0c. The prouduct of the rotan kiln called cement clinker. which is cooled, mixed with a few percent of gypsum and ground to a very fine powder.