What are the initial and final setting times of cement ? How are they experimentally determined ?
Initial Setting Time:-
It is regarded as the time elapsed between the moment that the water is added to cement to the time that the paste starts losing its plasticity.
Water added 
85 % of P = 0.85;
Plunger 1 mm sq. plunger (Vicat’s apparatus)
Minimum time 30 mins.
Final Setting Time:-
It is defined as the time elapsed between from adding water to the time that the paste completely looses its plasticity.
Plunger 1 mm circular Plunger.
Maximum time 10 hrs.
Short notes on :
Short notes on :
What are flaky and elongated aggregates? How can the shape of aggregate influence strength of concrete? Following is the result of a sieve analysis of 500 gm aggregate:
| IS sieve size | 10 mm | 4.75 mm | 2·36 mm | 1·18 mm | 600 micron | 300 micron | 150 micron | lower than 150 micron |
| Weight retained in gm | 0 | 10 | 50 | 50 | 95 | 175 | 85 | 35 |
Find out the 'Fineness Modulus' of the sample
Differentiate between creep and shrinkage of concrete.
