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Types of Cement For engineering purposes, there are many types of cement but in general, ‘Ordinary Portland Cement’ (OPC) which is available in three grades should be used for house construction 33 Grade Ordinary Portland Cement: This ordinary 'Portland' cement is used maximum in the country. It is more suitable cement for masonry and general concrete works where the members are not taken to very high stresses. It is not suitable where ‘Sulphate’ is in the soil or in the ground water. 43 Grade Ordinary Portland Cement: 43 grades of cement are used where high early strength in 1 to 28 days range is required. These days the ‘Structural Engineers’ propose these cements mainly for RCC works where a member takes high tensile stress. 53 Grade Ordinary Portland Cement: 53 grades of cement are used where high early strength in 1 to 28 days range is required. These days ‘Structural Engineers’ propose these cements mainly for RCC works, where a member takes high tensi...

FIELD TESTS ON CEMENT Field tests on cements are carried to know the quality of cement supplied at site. It gives some idea  about cement quality based on colour, touch and feel and other tests. The following are the field tests on cement: (a) The colour of the cement should be uniform. It should be grey colour with a light greenish shade. (b) The cement should be free from any hard lumps. Such lumps are formed by the absorption of  moisture from the atmosphere. Any bag of cement containing such lumps should be rejected. (c) The cement should feel smooth when touched or rubbed in between fingers. If it is felt rough, it  indicates adulteration with sand. (d) If hand is inserted in a bag of cement or heap of cement, it should feel cool and not warm. (e) If a small quantity of cement is thrown in a bucket of water, the particles should float for some  time before it sink. (f) A thick paste of cement with water is made on a piece of glass plate and it is kep...