Aggregate crushing value gives a relative measure of the resistance of an aggregate to crushing under a gradually applied compressive load. The aggregate crushing value should not exceed 45% for aggregate used for concrete other than for wearing surfaces, and 30 % for concrete for wearing surfaces, such as runways, roads
· The apparatus of the aggregate impact value test consists of: A testing machine weighing 45 to 60 kg and having a metal base with a plane lower surface of not less than 30 cm in diameter. Level and plane concrete floor of minimum 45 cm thickness are used to support it. The base of the machine should also have provisions for fixing its base.