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FA C following methods (listed in order of preference): 9.2.1 If the material is such that it can be manipulated and handled without significant moisture loss, the material should be mixed and then reduced to the required size by quartering or splitting. 9.2.2 If the material is such that it cannot be thoroughly mixed and/or split, form a stockpile of the material, mixing as much as possible. Take at least five portions of material at random locations using a sampling tube, shovel, scoop, trowel, or similar device appropriate to the maximum particle size present in the material. Combine all the portions for the test specimen. 9.2.3 If the material or conditions are such that a stockpile cannot be formed, take as many portions of the material as possible at random locations that will best represent the moisture condition. Combine all the portions for the test specimen. 9.3 Intact samples such as block, tube, split barrel; and the like, obtain the test specimen by one of the following methods depending on the purpose and potential use of the sample. 9.3.1 Carefully trim at least 3 mm of material from the outer surface of the sample to see if material is layered and to remove material that is drier or wetter than the main portion of the sample. Then carefully trim at least 5 mm, or a thickness equal to the maximum particle size present, from the entire exposed surface or from the interval being tested. 9.3.2 Slice the sample in half. If material is layered see Section 9.3.3. Then carefully trim at least 5 mm, or a thickness equal to the maximum particle size present, from the exposed surface of one half, or from the interval being tested. Avoid any material on the edges that may be wetter or drier than the main portion of the sample. NOTE 4—Migration of moisture in some cohesionless soils may require that the full section be sampled. 9.3.3 If a layered material (or more than one material type is encountered), select an average specimen, or individual specimens, or both. Specimens must be properly identified as to location, or what they represent, and appropriate remarks entered on data sheets. 10. Procedure 10.1 Determine and record the mass of the clean and dry specimen container (and its lid, if used). 10.2 Select representative test specimens in accordance with Section 9. 10.3 Place the moist test specimen in the container and, if used, set the lid securely in position. Determine the mass of the container and moist material using a balance (See 6.2) selected on the basis of the specimen mass. Record this value. NOTE 5—To prevent mixing of specimens and yielding of incorrect results, all containers, and lids if used, should be numbered and the container numbers shall be recorded on the laboratory data sheets. The lid numbers should match the container numbers to eliminate confu- sion. NOTE 6—To assist in the oven -drying of large test specimens, they should be placed in containers having a large surface area (such as pans) and the material broken up into smaller aggregations. 10.4 Remove the lid (if used) and place the container with moist material in the drying oven. Dry the material to a 164 constant mass. Maintain the drying oven at 110 ± 5°C unlesq otherwise specified (see 1.3). The time required to obtain constant mass will vary depending on the type of material,:. size of specimen, oven type and capacity, and other factors., The influence of these factors generally can be established by good judgment, and experience with the materials being tested and the apparatus being used. Non 7—In most cases, drying a test specimen overnight (about 12 to 16 h) is sufficient. In cases where there is doubt concerning the adequacy of drying, drying should be continued until the change in mass after two successive periods (greater than 1 h) of drying is an insignifi- cant amount (less than about 0.1 %). Specimens of sand may often be dried to constant mass in a period of about 4 h, when a forced -draft oven is used. NOTE 8—Since some dry materials may absorb moisture from moist specimens, dried specimens should be removed before placing moist specimens in the same oven. However, this would not be applicable if the previously dried specimens will remain in the drying oven for an additional time period of about 16 h. 10.5 After the material has dried to constant mass remove the container from the oven (and replace the lid if used). Allow the material and container to cool to room tempera- ture or until the container can be handled comfortably with bare hands and the operation of the balance will not be affected by convection currents and/or its being heated. Determine the mass of the container and oven -dried material using the same balance as used in 10.3. Record this value. Tight fitting lids shall be used if it appears that the specimen is absorbing moisture from the air prior to determination of its dry mass. N(ra: 9—Cooling in a desiccator is acceptable in place of tight fitting lids since it greatly reduces absorption of moisture from the atmosphere during cooling especially for containers without tight fitting lids. 11. Calculation 11.1 Calculate the water content of the material as fol- lows: w=1(M'W,—M")/(M,,.—MAX 100=M x 100 , where: W = water content, M,,,,, = mass of container and wet specimen, g, M,., = mass of container and oven dry specimen, g, M, = mass of container, g, M,, = mass of water (M,, = M,,,,S — Mid,), g, and M, = mass of solid particles (MS = Mid, — M,), g. 12. Report 12.1 The report (data sheet) shall include the following: 12. 1.1 Identification of the sample (material) being tested, such as boring number, sample number, test number, container number etc. 12.1.2 Water content of the specimen to the nearest 1, % or 0.1 %, as appropriate based on the minimum sample used. If this method is used in concert with another method, the water content of the specimen should be reported to the value required by the test method for which the water content is being determined. 12.1.3 Indicate if test specimen had a mass less than the minimum indicated in 8.2.