Determining the Moisture Content of Soil and Rock by Mass (Conventional Oven Method) - Soil Properties: Testing, Measurement, and Evaluation - page 40

present. Such a definition would be undesirable, because moisture con-
tent would then be based on a varying quantity of moist mass of soil
rather than a constant quantity of oven-dried soil. Stated another
way, with the incorrect definition, the moisture content would not be
directly proportional to the mass of water present. With the correct
definition given by Eq. (4-1), moisture content is directly proportional
to the mass of water present. This characteristic makes moisture con-
tent, as defined by Eq. (4-1), one of the most useful and important soil
parameters.

Drying oven (with accurate temperature control and temperature
gage)
Balance (with accuracy to 0.01 g)
Containers (e.g., tin or aluminum moisture cans with lids)
Desiccator
Container-handling apparatus: gloves, tongs, or suitable holder for
moving and handling hot containers after drying
Miscellaneous: knives, spatulas, scoops, quartering cloth, sample
splitters, etc.

APPARATUS
AND SUPPLIES

(1) Soil samples shall be preserved and transported in accordance
with ASTM Test Method D 4220 Groups B, C, or D soils. Rock sam-
ples shall be preserved and transported in accordance with Prac-
tice D 5079 section 7.5.2, Special Care Rock. Keep the samples that
are stored prior to testing in noncorrodible airtight containers at a
temperature between approximately 3° and 30°C and in an area
that prevents direct contact with sunlight. Disturbed samples in
jars or other containers shall be stored in such a way as to reduce
moisture condensation on the insides of the containers.

SAMPLES [1]

(2) The water content determination should be done as soon as
practicable after sampling, especially if potentially corrodible con-
tainers (such as thin-walled steel tubes, paint cans, etc.) or plastic
sample bags are used.

TEST
SPECIMEN [1]

(1) For water contents being determined in conjunction with an-
other ASTM method, the specimen mass requirement stated in
that method shall be used if one is provided. If no minimum speci-
men mass is provided in that method, then the values given below
shall apply.

(2) The minimum mass of moist material selected to be represen-
tative of the total sample is based on visual maximum particle size
in the sample and the Method (Method A or B) used to record the
data. Minimum specimen mass and balance readability shall be in
accordance with Table 4-1.