Standard Practice for Correction of Unit Weight and Water Content for Soils Containing Oversize Particles

Importancia y uso:

4.1 Compaction tests on soils performed in accordance with Test Methods D698, D1557, D4253, and D7382 place limitations on the maximum size of particles that may be used in the test. If a soil contains cobbles or gravel, or both, test options may be selected which result in particles retained on a specific sieve being discarded (for example the 4.75-mm [No. 4], the 19-mm [³/₄-in.] or other appropriate size) and the test performed on the finer fraction. The unit weight-water content relations determined by the tests reflect the characteristics of the actual material tested, and not the characteristics of the total soil material from which the test specimen was obtained.

4.2 It is common engineering practice to use laboratory compaction tests for the design, specification, and construction control of soils used in earth construction. If a soil used in construction contains large particles, and only the finer fraction is used for laboratory tests, some method of correcting the laboratory test results to reflect the characteristics of the total soil is needed. This practice provides a mathematical equation for correcting the unit weight and water content of the finer fraction of a soil, tested to determine the unit weight and water content of the total soil.

4.3 Similarly, as utilized in Test Methods D1556/D1556M, D2167, D6938, D7698, and D7830/D7830M, this practice provides a means for correcting the unit weight and water content of field compacted samples of the total soil, so that values can be compared with those for a laboratory compacted finer fraction.

Note 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.

Note 3: When this practice is used for construction control, the using agency should specify whether the maximum unit weight value used for reference is the unit weight including oversize fraction or the unit weight of the finer fraction. Calculated values of percent compaction based on this correction practice will vary depending on which unit weight value is used for reference.

Subcomité:

D18.03

Referida por:

D5080-20, D8153-22, D4546-21, D0698-12R21, D8167_D8167M-23E01, D1557-12R21, D0698-12R21, D7830_D7830M-14R21E01, D4546-21, D1557-12R21, D0698-12R21

Volúmen:

04.08

Número ICS:

93.020 (Earth works. Excavations. Foundation construction. Underground works)

Palabras clave:

compaction; oversize particles; relative density (specific gravity) (oven dried); unit weight; water content;