AASHTO T 112:2021 Standard Method of Test for Clay Lumps and Friable Particles in Aggregate

AASHTO T 112:2021 Standard Method of Test for Clay Lumps and Friable Particles in Aggregate.
1.1. This method covers the approximate determination of clay lumps and friable particles
in aggregates. This method is intended for evaluating aggregates that are nominally smaller than 21n.
Note 1—It is intended that this procedure will be conducted concurrently with T 27, when results from both procedures are desired. If that option is elected, additional sieves to those required in Section 6.3 will need to be incorporated; however, all of the material passing the 4.75 mm (No. 4) sieve at the completion of initial sieving and separation will be recombined prior to continuation of this procedure.
SAMPLES
Sample the aggregate in accordance with R 90. The mass of the field sample shall be the mass shown in R 90 or four times the mass required in Sections 5.3 and 5.4, whichever is greater.
5.2. Thoroughly mix the sample and reduce it to an amount suitable for testing using the applicable procedures described in R 76. The sample for testing shall meet the minimum mass required by Table I when dry and shall be the end result of the reduction. Reduction to an exact predetermined mass shall not be permitted.
5.3. Fine Aggregate—For a fine aggregate sample, only the material coarser than 2.00 mm (No. 10) sieve shall be tested. The size of the test sample of aggregate, after drying. shall be a minimum of 300g.
5.4. coarse Aggregate or coarse and Fine Aggregates Mixtures—-The approximate sample mass shall be determined by choosing the largest sieve to retain greater than 5 percent from the results of T 27. The mass of the test sample of aggregate shall conform with the requirements of Table 1.
Note 2—Excess agitation may lead to an incorrect result of the test method due to potentially breaking down clay lumps and friable particles that would otherwise be identified in this test method.
5.6. Dry the sample to constant mass according to T 255 at a 110 ± 5°C (230 ± 9°F).
6. PROCEDURE
6.1. Separate the test sample into different sizes using the following sieves: 37.5 mm (11/2 in.), 12.5 mm (V2 in.), 4.75 mm (No. 4) and 2.00 mm (No. 10).
6.2. Each separated portion may then be reduced again, according to the procedures described in R 76. After reduction, each portion shall weigh not less than indicated in Table 2. If the separating of the original sample provides less than the amount indicated in Table 2 tbr any separated portion. no reduction is allowed for that portion.AASHTO T 112 pdf download.