AS 1141.3.1:2021 pdf free download – Methods for sampling and testing aggregates Method 3.1: Sampling – Aggregates

AS 1141.3.1:2021 pdf free download – Methods for sampling and testing aggregates Method 3.1: Sampling – Aggregates.
Section 3 Terms and definitions
For the purpose of this document, the terms and definitions given in AS 1141.1 and the lollowing apply.
3.1
body ol material
material source from which a representative sample is to be obtained
Note 1 to entry: The body of material includes, but is not restricted to, stockpiles, rock piles, banks. sills, rock laces or outcrop.
competent person
person who has acquired, through education, training, qualification or experience, or a combination of these, the knowledge and skills to perform the task required
3.3
lot
discrete and defined quantity of material produced by a consistent process
Note 1 to entry: The lot is the fundamental division ol a body of aggregate for which material properties are determined. A lot consists of a homogeneous product and may be lurther de(ined by the length ot the production run or by mass.
3.4
may
indicates the existence of an option
3.5
sampling scheme
set of documented instructions that, as a minimum, establishes the following for each sample:
(a) Material to be sampled and the size of sample required.
(b) Purpose for obtaining the sample.
(c) Size and description of the lot(s), llapplicable,
(d) Sampling procedure to be used.
(e) Sampling location.
(f) Location of sampling Increments for each sample.
(g) Testing required on the sample collected.
(h) Details of sample dispatch.
Note ito entry: For further information on sampling suhcmcs, see Appendix C.
3.6
section
part of the main body of material, the main body being regarded as divided into sections of about equal volume
3.7
shall
indicates that a statement is mandatory
3.8
should
indicates a rccommcndation
(f) Material shall he fed to the divider from alternate sides on each successive split to reduce any
systematic bias in the splitting process.
6.5.3 Reduction by rotary sample divider
A mechanical rotary sample divider may be used in place of a riffle type sample divider.
The procedure for sample reduction by rotary division shall be as follows:
(a) Place the sampic Into the hopper of the rotary divider, ensuring that the opcnlng at the bottom of the hopper Is large enough to prevent bridging.
(b) Ensure that the opening of the segment or cutter lips at any point where it intersects the stream is a minimum of three times the nominal size of the material.
(c) Ensure that the speed of the divider at any point where ft Intersects the stream Is constant and no more than 0.6 rn/s.
(d) Activate the turntable or cutter prior to commencing the feed of the material.
(e) Allow a minimum of 20 passes of the receiving segment or cutter during the material feed (0 Continue rotation of the turntable or cutter until the material feed has been completed. NOTE 1 Other types of mechanical sample dividers may be used provided these dividers conform to the requirements of this document or AS 4433.1. and do not introduce bias.
NOTE 2 It may he necessary to dry the aggregate to a surface dry condition prior to spltttlngto avoid segregation and to allow the aggreg.ltc to flow through the splitter.
6.5.4 ReductIon by quartering
For reduction by quartering, aggregates shall be mixed and quartered on a hard, smooth clean surface. Except where the moisture content is to be determined, aggregates should be damped by the addition of potable water before mixing if the aggregate is dry enough to create dust when mixing.
The increments forming the sample shall be:
(a) Thoroughly mixed by heaping them into a cone and turning over to form a new cone until the operation has been carried out three times.
(b) Each cone shall be formed by depositing each scoopful of the material on the apex of the cone, so that the portions which slide down the sides will be distributed as evenly as possible.
(c) The centre of the cone will not be displaced.
(d) lisome of the large pieces of aggregate roll and scatter round the base, these shall be pushed hack to the edge of the cone.
The third cone formed from the mixed sample shall be flattened by repeated vertical insertions of the edge of a shovel or board, commencing about the centre and working radially round the cone, the shovel or board being lifted clear olthe material after each insertion. The flattened heap shall be—
(i) uniform in thickness;
(ii) uniform in diameter, and
(lii) the centre of the heap shall coincide with the centre of the original cone.
The flattened heap shall then be quartered along two diameters which intersect at right angles as follows.