ASTM D75/D75M-19 pdf free download.Standard Practice for Sampling Aggregates.
1.1 This practice covers sampling of coarse and tine aggregates lbr the following purposes:
1.1.1 Preliminary investigation of the potential source of supply.
I 1 .2 Control of the product at the source of supply.
1.1 .3 Control of the operations at the site of use, and
1.1.4 Acceptance or rejection of the materials.
1.2 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.
1.3 The values stated in either SI units or inch-pound units are to he regarded separately as standard. The values stated in each system may not be exact equivalents: therefore, each system shall be used independently of the other. Combining values from the two systems may result in floflconft)rmancc with the standard.
5 Securing Samples
5.1 General—Where practicable, samples to be tested for quality shall be obtained from the finished product. Samples from the finished product to be tested for abrasion loss shall not be subject to further crushing or manual reduction in particle size in preparation for the abrasion test unless the size of the finished product is such that it requires further reduction for testing purposes.
5.2 Inspection—The material to be sampled shall be visually inspected to determine discernible variations. If any discernible variations are noted, corrective action shall he taken to establish homogeneity in the material prior to sampling. If it is necessary to indicate the degree of variability existing within the main pile, separate samples shall be drawn from separate areas of the pile. The seller shall provide suitable equipment needed for proper inspection and sampling.
5.3 Procedure:
5.3. 1 Sampling from a Flowing Aggregate Strew;i (Bimis or Belt Discha,:e)—Select units to be sampled by a random method, such as Practice D3665, from the production. Obtain at least three approximately equal increments, selected at random from the unit being sampled, and combine to form a field sample whose mass equals or exceeds the minimum recommended in 5.4.2. Take each increment from the entire cross section of the material as it is being discharged. It is usually necessary to have a special device constructed for use at each particular plant. This device consists of a pan of sufficient size to intercept the entire cross section of the discharge stream and hold the required quantity of material without overflowing. A set of rails may he necessary to support the pan as ii is passed under the discharge stream. Insofar as is possible, keep bins continuously full or nearly full to reduce segregation.
NOTF 4—Sampling the ininal discharge or the final tw Ions from a bin or conveyor belt increases the chances of obtaining segregated maerial and should be avoided.
5.3.2 Swnplinç fromu the (‘onvevor Belt—Select units to be sampled by a random method, such as Practice D3665. from the production. Obtain at least three approximately equal increments, selected at random, from the unit being sampled and combine to form a field sample whose mass equals or exceeds the minimum recommended in 5.4.2.ASTM D75/D75M pdf download.