Short notes on :
SLUMP TEST:- slump cone test is done to determine the workability of concrete or how much the concrete is fluid or plastic . This test is suitable for high workability mix.
PROCEDURE:-
Now the slump cone is raised vertically but slowly and allowed the concrete to subside. This subsidence is referred as slump of concrete.
Value- 100mm to 190mm {workable concrete}
COMPACTING FACTOR TEST:- This test is useful for concrete mix of very low workability and when concrete is to be compacted by vibration.
COMPACTING FACTOR = wt. of partially compacted concrete / wt. of fully compacted concrete
PROCEDURE:-
CRUSHING TEST:- It is a relative measure of resistance of an aggregate to crushing under gradually applied compressive load. Crushing value of aggregate is restricted to 30% as per IRC.
IMPACT TEST:- It is a measure of resistance of an aggregate to sudden impact or shock i.e. it is done to measure the toughness of an aggregate. Impact value should not normally exceed 40% as per IRC.
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
Give the physical characteristics of 53 grade OPC.
Write notes on Mixing and Mixer machines of concrete.
