Field Test

 Field tests on cement are carried to know the quality of cement supplied at the site. It gives some idea about cement quality based on colour, touch and feels and other tests.



Tests on Cement at the Construction site:

  • Colour test: The colour of the cement should normally be greenish-grey.
  • Presence of lumps:

    • Due to the moisture from the atmosphere, cement develops lumps. But it’s not good to use that for construction. 

    • Open the bag and take a good look at the cement. There should not be any visible lumps

  • Adulteration test:
    • This test is performed by feeling the cement with fingers. It should feel smooth when rubbed in between fingers. 
    • If it feels rough, it implies that the cement is adulterated with sand.
  • Temperature test:
    • This test involves inserting the hand in the bag to check its temperature. It must be giving you a cool feeling.
    • If it’s warm inside, then it indicates that the process of hydration is taking place.
  • Float tests:
    • This test consists of throwing a handful of cement in the bucket full of water. The cement particles should float for some time before sinking.
  • Strength test:

    • If the block will not show any failure, then the cement is of good quality.

    • It is then placed on supports 150mm apart and it is loaded with a weight of about 34kg.
    • If the block will not show any failure, then the cement is of good quality. 
  • Setting test:
    • In this test, a thick paste is prepared by mixing cement and water and is placed on a piece of glass plate
    • This is kept underwater for 24hours. After this, it should set and not crack.
  • Date of packing.:
    • The strength of cement reduces with time, so it is important to check the manufacturing date of the cement. 
    • The general fact is that the cement should be used before 90 days from the date of manufacturing.

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