Cement use in sit and testing , type of cement ,menufectring of cement

cement

1. CEMENT Cement is a material which has cohesive and adhesive properties in the presence of water Chemical Composition of Raw Materials Oxide Composi tion (%) Lime, CaO 60 – 65 Function Deficiency reduces strength and setting time Silica, SiO2 Alumina, Al2 O3 Iron oxide Fe2 O3 Magnesia, MgO Soda and Potash Na2 O and K2 O Sulphur trioxide SO3 17 – 25 3 – 8 0.5 – 6 0.5 – 4 0.5 – 1 1 – 2 Excess of it causes slow setting Responsible for quick setting, excess of it lowers strength Gives colour and Fe2 O3 Magnesia, MgO Soda and Potash Na2 O and K2 O Sulphur trioxide SO3 17 – 25 3 – 8 0.5 – 6 0.5 – 4 0.5 – 1 1 – 2

2. Excess of it causes slow setting Responsible for quick setting, excess of it lowers strength Gives colour and helps in fusion of different ingredients Colour and hardness If in excess causes efflorescence and cracking Makes cement sounesh Fe2 O3 Magnesia, MgO Soda and Potash Na2 O and K2 O Sulphur trioxide SO3 17 – 25 3 – 8 0.5 – 6 0.5 – 4 0.5 – 1 1 – 2 Excess of it causes slow setting Responsible for quick setting, excess of it lowers strength Gives colour and helps in fusion of different ingredients Colour and hardness If in excess causes efflorescence and cracking Makes cement soun

3. Types of Cement C 1. Portland cement: Classified on the basis of manufacturing as 33 grade, 43 grade and 53 grade. On the basis of compressive strength, As per IS 10262 classified from grade A to F. 2. Rapid hardening cement: More C3 S and less C2 S as compared to OPC Not-used in mass concrete Large Shrinkage 3. Extra Rapid hardening cement:

4. Rapid hardening cement + 2% CaCl2 Especially used in cold weather Excessive Shrinkage Not used in Pre-Stressed concrete 4 . High Alumina cement: Bauxite (40%), Lime stone (40%) Iron oxide (15%) Particularly suitable t