1、Designation: D2216 10Standard Test Methods forLaboratory Determination of Water (Moisture) Content ofSoil and Rock by Mass1This standard is issued under the fixed designation D2216; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 These test methods cover
3、the laboratory determinationof the water (moisture) content by mass of soil, rock, andsimilar materials where the reduction in mass by drying is dueto loss of water except as noted in 1.4, 1.5, and 1.7. Forsimplicity, the word “material” shall refer to soil, rock oraggregate whichever is most applic
4、able.1.2 Some disciplines, such as soil science, need to deter-mine water content on the basis of volume. Such determina-tions are beyond the scope of this test method.1.3 The water content of a material is defined in 3.2.1.1.4 The term “solid material” as used in geotechnicalengineering is typicall
5、y assumed to mean naturally occurringmineral particles of soil and rock that are not readily soluble inwater. Therefore, the water content of materials containingextraneous matter (such as cement etc.) may require specialtreatment or a qualified definition of water content. In addition,some organic
6、materials may be decomposed by oven drying atthe standard drying temperature for this method (110C).Materials containing gypsum (calcium sulfate dihydrate) orother compounds having significant amounts of hydrated watermay present a special problem as this material slowly dehy-drates at the standard
7、drying temperature (110C) and at verylow relative humidity, forming a compound (such as calciumsulfate hemihydrate) that is not normally present in naturalmaterials except in some desert soils. In order to reduce thedegree of dehydration of gypsum in those materials containinggypsum or to reduce dec
8、omposition in highly/fibrous organicsoils, it may be desirable to dry the materials at 60C or in adesiccator at room temperature. Thus, when a drying tempera-ture is used which is different from the standard dryingtemperature as defined by this test method, the resulting watercontent may be differen
9、t from the standard water contentdetermined at the standard drying temperature of 110C.NOTE 1Test Method D2974 provides an alternate procedure fordetermining water content of peat materials.1.5 Materials containing water with substantial amounts ofsoluble solids (such as salt in the case of marine s
10、ediments)when tested by this method will give a mass of solids thatincludes the previously soluble dissolved solids. These mate-rials require special treatment to remove or account for thepresence of precipitated solids in the dry mass of the specimen,or a qualified definition of water content must
11、be used. Forexample, see Test Method D4542 regarding information onmarine sediments.1.6 This test standard requires several hours for properdrying of the water content specimen. Test Methods D4643,D4944 and D4959 provide less time-consuming processes fordetermining water content. See Gilbert2for det
12、ails on thebackground of Test Method D4643.1.7 Two test methods are provided in this standard. Themethods differ in the significant digits reported and the size ofthe specimen (mass) required. The method to be used may bespecified by the requesting authority; otherwise MethodAshallbe performed.1.7.1
13、 Method AThe water content by mass is recorded tothe nearest 1 %. For cases of dispute, Method A is the refereemethod.1.7.2 Method BThe water content by mass is recorded tothe nearest 0.1 %.1.8 This standard requires the drying of material in an oven.If the material being dried is contaminated with
14、certainchemicals, health and safety hazards can exist. Therefore, thisstandard should not be used in determining the water content ofcontaminated soils unless adequate health and safety precau-tions are taken.1.9 UnitsThe values stated in SI units shall be regarded asstandard excluding theAlternativ
15、e Sieve Sizes listed inTable 1.No other units of measurement are included in this test method.1.10 Refer to Practice D6026 for guidance concerning theuse of significant figures that shall determine whether Method,A or B is required. This is especially important if the watercontent will be used to ca
16、lculate other relationships such as1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.03 on Texture, Plasticityand Density Characteristics of Soils.Current edition approved July 1, 2010. Published August 2010. Origina
17、llyapproved in 1963. Last previous edition approved in 2005 as D221605. DOI:10.1520/D2216-10.2Gilbert, P.A., “Computer Controlled Microwave Oven System for Rapid WaterContent Determination,” Tech. Report GL-8821, Department of the Army, Water-ways Experiment Station, Corps of Engineers, Vicksburg, M
18、S, November 1988 .1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.moist mass to dry mass or vice versa, wet unit weight to dryunit weight or vice versa, and total dens
19、ity to dry density orvice versa. For example, if four significant digits are requiredin any of the above calculations, then the water content must berecorded to the nearest 0.1 %. This occurs since 1 plus thewater content (not in percent) will have four significant digitsregardless of what the value
20、 of the water content is; that is, 1plus 0.1/100 = 1.001, a value with four significant digits.While, if three significant digits are acceptable, then the watercontent can be recorded to the nearest 1 %.1.11 This standard does not purport to address all of thesafety concerns, if any, associated with
21、 its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D653 Terminology Relating to Soil, Rock, and ContainedFluidsD2974 Te
22、st Methods for Moisture,Ash, and Organic Matterof Peat and Other Organic SoilsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4220 Practices for Preserving and Transporting SoilSamplesD4318 Test M
23、ethods for Liquid Limit, Plastic Limit, andPlasticity Index of SoilsD4542 Test Method for Pore Water Extraction and Deter-mination of the Soluble Salt Content of Soils by Refrac-tometerD4643 Test Method for Determination of Water (Moisture)Content of Soil by Microwave Oven HeatingD4753 Guide for Eva
24、luating, Selecting, and SpecifyingBalances and Standard Masses for Use in Soil, Rock, andConstruction Materials TestingD4944 Test Method for Field Determination of Water(Moisture) Content of Soil by the Calcium Carbide GasPressure TesterD4959 Test Method for Determination of Water (Moisture)Content
25、of Soil By Direct HeatingD5079 Practices for Preserving and Transporting RockCore SamplesD6026 Practice for Using Significant Digits in GeotechnicalDataD7263 Test Methods for Laboratory Determination of Den-sity (Unit Weight) of Soil SpecimensE145 Specification for Gravity-Convection and Forced-Vent
26、ilation Ovens3. Terminology3.1 Refer to Terminology D653 for standard definitions ofterms.3.2 Definitions:3.2.1 water content by mass (of a material)the ratio of themass of water contained in the pore spaces of soil or rockmaterial, to the solid mass of particles in that material,expressed as a perc
27、entage. A standard temperature of 110 65C is used to determine these masses.3.3 Definitions of Terms Specific to This Standard:3.3.1 constant dry mass (of a material)the state that awater content specimen has attained when further heatingcauses, or would cause, less than 1 % or 0.1 % additional loss
28、in mass for Method A or B respectively. The time required toobtain constant dry mass will vary depending on numerousfactors. The influence of these factors generally can be estab-lished by good judgement, and experience with the materialsbeing tested and the apparatus being used.4. Summary of Test M
29、ethod4.1 A test specimen is dried in an oven at a temperature of110 6 5C to a constant mass. The loss of mass due to dryingis considered to be water. The water content is calculated usingthe mass of water and the mass of the dry specimen.5. Significance and Use5.1 For many materials, the water conte
30、nt is one of the mostsignificant index properties used in establishing a correlationbetween soil behavior and its index properties.5.2 The water content of a material is used in expressing thephase relationships of air, water, and solids in a given volumeof material.5.3 In fine-grained (cohesive) so
31、ils, the consistency of agiven soil type depends on its water content. The water content3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summa
32、ry page onthe ASTM website.TABLE 1 Minimum Requirements for Mass of Test Specimen, and Balance ReadabilityAMaximum Particle Size (100 % Passing)Method AWater Content Recorded to 61%Method BWater Content Recorded to 60.1 %SI UnitSieve SizeAlternative SieveSizeSpecimenMassBalanceReadability (g)Specime
33、nMass (g)BalanceReadability (g)75.0mm 3in 5kg 10 50kg 1037.5 mm 1-12 in. 1 kg 10 10 kg 1019.0 mm34 in. 250 g 1 2.5 kg 19.5 mm38 in. 50 g 0.1 500 g 0.14.75 mm No. 4 20 g 0.1 100 g 0.12.00 mm No. 10 20 g 0.1 20 g 0.01AIf water content data is to be used to calculate other relationships, such as moist
34、or dry mass, wet or dry unit weight or total or dry density, then specimen mass upto 200 g must be determined using a balance accurate to 0.01 g.D2216 102of a soil, along with its liquid and plastic limits as determinedby Test Method D4318, is used to express its relative consis-tency or liquidity i
35、ndex.NOTE 2The quality of the result produced by this standard isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Agencies that meet thecriteria of Practice D3740 are generally considered capable of competentand objective testing/sa
36、mpling/inspection/etc. Users of this standard arecautioned that compliance with Practice D3740 does not in itself ensurereliable results. Reliable results depend on many factors; Practice D3740provides a means of evaluating some of those factors.6. Apparatus6.1 Drying OvenVented, thermostatically-co
37、ntrolled,preferably of the forced-draft type, meeting the requirements ofSpecification E145 and capable of maintaining a uniformtemperature of 110 6 5C throughout the drying chamber.6.2 BalancesAll balances must meet the requirements ofSpecification D4753 and this section. A Class GP1 balance of0.01
38、 g readability is required for specimens having a mass ofup to 200 g (excluding mass of specimen container) and a ClassGP2 balance of 0.1 g readability is required for specimenshaving a mass over 200 g. However, the balance used may becontrolled by the number of significant digits needed (see1.10).6
39、.3 Specimen ContainersSuitable containers made of ma-terial resistant to corrosion and change in mass upon repeatedheating, cooling, exposure to materials of varying pH, andcleaning. Unless a dessicator is used, containers with close-fitting lids shall be used for testing specimens having a mass ofl
40、ess than about 200 g; while for specimens having a massgreater than about 200 g, containers without lids may be used(see Note 3). One uniquely numbered (identified) container ornumber-matched container and lid combination as required isneeded for each water content determination.NOTE 3The purpose of
41、 close-fitting lids is to prevent loss of moisturefrom specimens before initial mass determination, and to prevent absorp-tion of moisture from the atmosphere following drying and before finalmass determination.6.4 Desiccator (Optional)A desiccator cabinet or largedesiccator jar of suitable size con
42、taining silica gel or anhydrouscalcium sulfate. It is preferable to use a desiccant that changescolor when it needs to be reconstituted.NOTE 4Anhydrous calcium sulfate is sold under the trade nameDrierite.6.5 Container Handling Apparatus, heat resistant gloves,tongs, or suitable holder for moving an
43、d handling hot contain-ers after drying.6.6 Miscellaneous, knives, spatulas, scoops, quarteringcloth, wire saws, etc., as required.7. Samples7.1 Soil samples shall be preserved and transported inaccordance with Practice D4220 Section 8 Groups B, C, or Dsoils. Rock samples shall be preserved and tran
44、sported inaccordance with Practice D5079 section 7.5.2, Special CareRock. Keep the samples that are stored prior to testing innon-corrodible airtight containers at a temperature betweenapproximately 3 and 30C and in an area that prevents directcontact with sunlight. Disturbed samples in jars or othe
45、rcontainers shall be stored in such a way as to minimizemoisture condensation on the insides of the containers.7.2 The water content determination should be done as soonas practicable after sampling, especially if potentially corrod-ible containers (such as thin-walled steel tubes, paint cans, etc.)
46、or plastic sample bags are used.8. Test Specimen8.1 For water contents being determined in conjunction withanother ASTM method, the specimen mass requirement statedin that method shall be used if one is provided. If no minimumspecimen mass is provided in that method then the values givenbelow shall
47、apply. See Howard4for background data for thevalues listed.8.2 The minimum specimen mass of moist material selectedto be representative of the total sample is based on visualmaximum particle size in the sample and the Method (MethodA or B) used to record the data. Minimum specimen mass andbalance re
48、adability shall be in accordance with Table 1.8.3 Using a test specimen smaller than the minimum indi-cated in 8.2 requires discretion, though it may be adequate forthe purposes of the test. Any specimen used not meeting theserequirements shall be noted on the test data forms or test datasheets.8.4
49、When working with a small (less than 200 g) specimencontaining a relatively large gravel particle, it is appropriatenot to include this particle in the test specimen. However, anydiscarded material shall be described and noted on the test dataform/sheet.8.5 For those samples consisting entirely of intact rock orgravel-size aggregate, the minimum specimen mass shall be500 g. Representative portions of the sample may be brokeninto smaller particles. The particle size is dictated by thespecimen mass, the container volume and the balance beingused to determine co
