Standard Test Method for Determination of Water Content of Soil By Direct Heating

Importancia y uso:

5.1 The water content of a soil is used throughout professional practice both in the laboratory and in the field. The use of Test Methods D2216 for water content determination can be time consuming and there are occasions when a more expedient method is desirable. Drying by direct heating is one such method. Results of this test method have been demonstrated to be of satisfactory accuracy for use in field control testing, such as in the determination of water content, and in the determination of in-place dry unit weight of soils.

5.2 The principal objection to the use of the direct heating for water content determination is the possibility of overheating the soil, thereby yielding a water content higher than would be determined by Test Methods D2216. While not eliminating this possibility, the incremental drying procedure in this test method will reduce its effects. Some heat sources have settings or controls that can also be used to reduce overheating. Loose fitting covers or enclosures can also be used to reduce overheating while assisting in uniform heat distribution.

5.3 The behavior of a soil when subjected to direct heating is dependent on its mineralogical composition, and as a result, no one procedure is applicable for all types of soils or heat sources. The general procedure of this test method applies to all soils, but test details may need to be tailored to the soil being tested.

5.4 When this test method is to be used repeatedly on the same or similar soil from a given site, a correction factor can usually be determined by making several comparisons between the results of this test method and Test Methods D2216. A correction factor is valid when the difference is consistent for several comparisons, and is reconfirmed on a regular specified basis.

5.5 This test method is not appropriate when precise results are required, or when minor variations in water content will affect the results of other test methods, such as borderline situations where small variations in the measured water content could affect acceptance or rejection.

5.6 This test method is not appropriate for specimens known to contain flammable organics or contaminants, and other test methods should be utilized in these situations.

Note 1: 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 facility 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 assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.

Subcomité:

D18.08

Referida por:

C1893-24, D7380_D7380M-21, D3839-14R19, C1746_C1746M-24, E3317-22, E3373-24, D2937-24, F1815-11R18, E3318-24, D6758-18E01, D6938-23, D2216-19, F1668-16R22, D5874-24, E2277-14R19, D2216-19, D8167_D8167M-23E01, D7830_D7830M-14R21E01, D6938-23

Volúmen:

04.08

Número ICS:

13.080.40 (Hydrological properties of soil)

Palabras clave:

acceptance tests; compaction control; density; direct heating; laboratory moisture tests; moisture content; moisture control; quality control; rapid method; soil moisture; test procedure; water content;