Testing of Cement can be brought under two categories.
(a) Field Testing
(b) Laboratory Testing
It is sufficient to subject the cement to field tests whenit is trusted for minor works. The following are the field tests.
(a) Open and the bag and takea good look at the cement. There should not be any visiblelumps. The colour of the cement should normally be greening grey.
(b) Thrust your hand into the cement bag. It must give a coolfeeling. There should not be any lump inside.
(c) Take a pinch of cement andfeel between fingers. It should give a smooth and not a grittyfeeling.
(d) Take a handful of cement and through it in to a bucket full of water, the particles should float for some time before they sink.
(e) Take about 100 grams of cement and a small quantity ofwater and make a stiff paste. From the stiff paste , pat a cake with sharp edges. Put it on a glass plate and slowly take it under water with a bucket.See the shape of the cake is not disturbed while taking it down the bottom of the bucket. After 24 hours thecake should retain its original shape and at the same time it should also set and attain some strength.
If a sample of cement satisfies the above field tests it may be concluded that the cement is not bad.The above tests does not really indicates that the cement is really goodfor important works. For usingcement in important and majorworks it is incumbent on the part of the user to test the cement in the laboratory to confirm the requirements of the Standard Specifications with respect to its physical and chemical properties.The tests which are usually conducted in the Lab to confirm those properties are …
1 . Fineness Test
2. Initial and Final Setting Time Test
3. Shear Test
4. Soundness Test
5. Heat of Hydration Test
6. Chemical Composition Test
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