Determine of Aggregate Impact Value Test: BS 812

Experiment Name: Determine of Aggregate Impact Value Test: BS 812

Purpose of the test:  

The Impact value of an aggregate is the percentage loss of weight particles passing 2.36mm sieve by the application of load by means of 15 blows of standard hammer and drop, under specified test condition. AIV gives A relative measure of the resistance of an aggregate to sudden impact, which is differs from withstand to slowly applied compressive load .The value is great than 30, the result is may be   exceptional. Aggregate size 14mm is not appropriate to the AIV test.

Apparatus:

a. Impact testing machine:

i. A cylindrical hammer of 13.5kg (30 lbs) sliding freely between two vertical supports (guides).

ii. Decline automatically adjusted to the height of 0.38m.

iii. The Brass plate over which an open cylindrical steel cup of internal diameter 0.102m and 0.05m depth placed and fixed to the Brass pebble.

 b. Tamping rod of 10mm diameter and 230 long rounded at one end and pointed at the other end.

Materials:

Coarse aggregate.

Procedure of this Test:

a. Samples are weighted up to 600g.

 b. The aggregate of size 0.0125m – 0.0095m are fill up in the cylindrical measure in 3 strata folded using tamping rod for 25 times. perpendicular edge  used as the level of surface tamping rod.

c. The cylindrical measure was transferred to the brass plate.

d. The Trigger was escaped to flop down on the aggregate and gives 15 knock are subjected to  total of the given test .

e. Samples were sieved by 2.36mm sieve after removed from cup.

f. Weights of retain ad passing were measured.

Calculation:

Test Results:

This aggregate is passed by AIV test ,so the result is Strong and enough .

Discussion:

During the experiment, we do not face any major problem, so our getting result is not wrong. If our result is less than 30%, so the result is Strong and enough for this test.