AS 1141.11.1:2020 pdf download.Methods for sampling and testing aggregates Method 11.1: Particle size distribution – Sieving method.
6 Preparation of test portion
6.1 General
The minimum mass of test portion taken shall be in accordance with the nominal size of the aggregate in Table 1. The required test portion shall be obtained by sample division, no attempt being made to secure an exact predetermined mass.
6.2 Mixtures of coarse and fine aggregates
Mixtures of coarse and fine aggregates shall be separated into two sizes using a 4.75 mm test sieve. The portions obtained shall be measured out and tested separately. The size of the test portion for each fraction shall be in accordance with Table 1.
NOTE The percentage passing each sieve should be calculated on the basis of the total mass of the test portion making appropriate calculations to take into account the ratio of the mass of the fine fraction tested to the total material.
6.3 Preparation of test portion
Test portions may be tested without further preparation or may be washed over a 75 pm sieve after drying, see Clause 6.6.
6.4 Fillers for asphalt
Fillers for asphalt shall be separated on a 600 pm test sieve from material passing a 4.75 mm test sieve.
6.5 Drying
The test portions shall be dried to constant mass. The mass of each fraction or test portion (Mi) shall be determined and recorded.
6.6 Washing
With the exception of asphalt fillers (see Clause 7. Note 2) where an aggregate sample is tested for comparison with a document in which the passing 75 lIm size is specified, the test portion shall be washed over a 75 pm sieve as follows:
(a) Place the dried test portion in a dish or pan and add sufficient clean water to cover it.
NOTE 1 For materials that contain clay, a dispersing agent that does not react with the test portion may be used.
NOTE 2 The water used should not react with the aggregate.
(b) Vigorously agitate the contents without spilling the water to take the fine material into suspension and immediately pour the wash water through two sieves nested together with a guard sieve, e.g. 1.18 mm sieve, at the top and a 75 pm sieve below. Avoid, as far as possible, decantation of the coarse particles of the test portion.
(c) Continue agitation and washing until the water is clear in the pan. Wash all the remaining test portion over the nested guard sieve and 75 pm sieve using a low-pressure water jet. Ensure that no material is lost from the sides of the sieves. Use small portions for each washing to avoid overloading of the sieves.
NOTE 3 Where the amount of material finer than 2 pm is to be determined, the wash water from Steps (b) and (c) may be retained for use with the AS 1141.13 method. If a soluble, non-volatile dispersing agent has been used in Step (a), the result of AS 1141.13 is to be corrected proportionally for the mass of agent used.
(d) Dry the washed aggregate to constant mass. Determine and record the mass of the dried, washed aggregate (M2).AS 1141.11.1 pdf download.