Sample for test.
A
sample of about 1 kg for material having a nominal size from 10mm to 5mm
inclusive, or about 500 g if finer than 5 mm, shall be used. Aggregates which
have been artificially heated shall not normally be used. If such material is
used, that fact shall be stated in the report. Two test shall be made.
The
sample shall be thoroughly washes to remove all material finer than the 75 µm BS test
sieve (5.5.1.7) using the following procedure.
Place
the test sample in the container and add enough water to cover it. Agitate
vigorously the contents of the container and immediately pour the wash water
over the sieves, which have previously been wetted on both sides and arranged
with the coarser sieve on top.
The
agitation shall be sufficiently vigorous to result in the complete separation
from the coarse particles of all particles finer than 75 µm BS test sieve,
and to bring the fine material into suspension in order that it will be removed
by decantation of the wash water. Take care to avoid, as far as possible,
decantation of the coarse particles of the sample. Repeat the operation until
the wash water is clean. Return all material retained on the sieves to the
washed sample.
