This test is perform to check the initial and final setting time of cement. The initial setting time is determined so as to give sufficient time for various operations like mixing, transportation, placing and compaction of cement mortar or concrete.
The final setting time is determined to find that after laying the mortar or concrete, the hardening should be rapid so that the structure may be made in use as early as possible.
This test is performed as per IS 4031 Part 5 using Vicat appratus conforming to IS 5513.
Initial Setting Time:
The final setting time is determined to find that after laying the mortar or concrete, the hardening should be rapid so that the structure may be made in use as early as possible.
This test is performed as per IS 4031 Part 5 using Vicat appratus conforming to IS 5513.
Initial Setting Time:
- Take clean cement of about 400 g in weight sieved through IS sieve no 9.
- Add water at a rate of 0.85 P byweight of cement.
P = Percentage of water required for normal consistency.
- Start the stop clock as soon as the water is added to the cement.
- Filled the vicat mould in the same way as done while performing consistency test.
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Place the mould on the base plate of the apparatus centrally below the movable rod to which neddle is attached and brought in contact with the surface of the cement paste.
- Note the initial reading and release the rod quickly without any jerk and note the penetration.
In the begining, the needle will completely penetrate the cement paste.
- The procedure is repeated until the needle fails to penetrate the block for about 5 mm, measured from the bottom of the mould.
Note: While repeating the penetration process, the needle should be cleaned and released at a new place on the top of the surface.
Final Setting time:
- Replace the neddle of the vicat apparatus with annular attachment(Neddle F).
- Release it on the top surface of the mould at regular intervals and record the time.
In the begining, the needle and the collar will make impressions on the top of the paste.
- Note the time at which only needle leaves the impression and collar fails to do so.
Note: Clean the needle each time and the needle should be released at a new place in each trial.
P = Percentage of water required for normal consistency.
In the begining, the needle will completely penetrate the cement paste.
Note: While repeating the penetration process, the needle should be cleaned and released at a new place on the top of the surface.
In the begining, the needle and the collar will make impressions on the top of the paste.
Note: Clean the needle each time and the needle should be released at a new place in each trial.
Setting time of Different Cements in minutes
| Ordinary Portland Cement | Rapid Hardening Cement | Low Heat Cement | |
| Initial Setting Time | 30 | 30 | 60 |
| Final Setting Time | 600 | 600 | 600 |
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