Aggregate Crushing Value (ACV):

The resistance of aggregate to crushing under gradually applied compressive load is relatively measured in terms of aggregate crushing value. This test is more popular for representing the strength of aggregate. To determine the aggregate crushing value, a sample of aggregate passing by 12.5 mm and retained on 10 mm is taken. That sample of aggregate in saturated surface dry condition is filled in the cylindrical container in three layers by tamping each layer 25 times with tamping rod in standard manner and the weight of sample 'A' is taken. This aggregate sample (weighing 'A') is placed in the test apparatus and is uniformly loaded through a plunger up to a total load of 40 tons in 10 minutes. After removing the load the aggregate is taken out and sieved through 2.36 mm sieve. The weight 'B' of the fraction passing through 2.36 mm is taken.

Aggregate crushing value (ACV) is determined in percentage by:

ACV = B/A × 100

where, A = Weight of prepared aggregate sample, and

B = Weight of aggregate passing through 2.36 mm after applying the load. As per IS 383: 1970, the ACV should not be more than 45% for the concrete used for other than wearing surface, whereas ACV should be limited to 30% for the concrete used for wearing surface such as roads, runways and air field pavements.