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Abstract The cement denotes any kind of binding agent. The usefulness of cement lies in its ability to bind together pieces of gravel, crushed stone, or bricks, to give a hand mass. However, materials most commonly associated with this word are hydraulic cements of which Portland cement is the most familiar. When mixed with enough water form a plastic mass (paste), the mixture starts to set, looses its plasticity and becomes hard. The paste continues to harden and develops strength, volume stability and permeability to water. Portland cement in manufactured by intimately mixing a calcareous and an argillaceous material, burning at a clinkering temperature, up to 1450oC. The resulting clinker is cooled, mixed with about 5 percent of gypsum to regulate the setting of the cement, then ground together to a very fine powder. The major components of the clinker are tricalcium silicate or alite, 3CaO. SiO2 (C3S), β-dicalcium silicate or belite, 2CaO.SiO2 (β- C2S), tricalcium aluminate, 3CaO. Al2O3 (C3A) and tetracalcium aluminaferrite or ferrite solid solution, 4CaO. |