SETTING TIME TEST OF CEMENT

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Apparatus Required

Take 400 grams of cement sample and gauge with 0.85 times the water required of standard consistency .
Gauge it properly and fill the mould , within 3-5 minutes from the time of addition of water and smoth off the surface of the mould ,slightly shake the mould along with the base plate to expel air .
This cement block is known as test block, for determining intial setting time place the test block along with base plate in the vicat apparatus bearing the intial setting time needle , lower the needle till it comes in contact with the surface , then suddenly release it to completely pierce the test block, repeat the procedure until the neddle fails to pierce the last 5 mm of the test block , note the time .
Replace the needle , by another needle with an annular attachment of vicat apparatus , apply the needle gently into the surface of the test block, watch for condition during the time when on applying the needle , the needle makes an impression on the surface but the attachment does not.
The period elapsing between the time when water is added to the cement and the time at which the needle makes an impression on the surface of test block while the attachment fails to do so shall be the final setting time .