Part A

1. Obtain 25-30 lb. sample of freshly mixed concrete in accordance with ASTM C172.
2. Wash obtained sample of freshly mixed concrete over combination of 12" diameter ½ -inch and 3/8- inch sieves in general accordance with ASTM C117.
3. Weigh wet aggregate.
4. Remove non-specified aggregate and other deleterious materials in general accordance with ASTM C142.
5. Weigh remaining specified aggregate.
6. Percentage of non-specified aggregate is: 1 - (Specified aggregate weight/Total aggregate weight)

If percentage of non-specified aggregate in concrete mixes delivered from centrally batched concrete plants exceeds 3% by weight of the coarse aggregate fraction, or if percentage of non-specified aggregate in all other concrete mixes exceeds 2% by weight, place specified and non-specified aggregate in separate sample bays and return to the laboratory and complete Part B of the test.

Part B

1. Place specified and non-specified aggregate in separate sample bays.
2. Dry both aggregates in general accordance with ASTM C566.
3. Determine dry weight of specified and non-specified aggregates.
4. Final percentage of non-specified aggregate is: 1 - (Dry weight of specified aggregate/Dry weight of total aggregate)

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