1、Designation: D2974 07aD2974 13Standard Test Methods forMoisture, Ash, and Organic Matter of Peat and OtherOrganic Soils1This standard is issued under the fixed designation D2974; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、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.1. Scope*1.1 These test methods cover the measurement of moisture content, ash content, and organic matter in peats and ot
3、her organicsoils, such as organic clays, silts, and mucks. Test Method D2216 provides an alternative method for determining moisture contentin mineral soils and rock.1.1.1 Test Method AMethod A moisture Moisture is determined by drying peat or organic sample at 105 C.110 6 5C.1.1.2 Test Method BMeth
4、od B Alternative moisture method which removes the total moisture in two steps: (1)(1)evaporation of moisture at room temperature, (2)(2) subsequent oven drying of air dried sample at 105 C. 110 6 5C. This methodis used when the peat is to be used as fuel.1.1.3 Test Method CMethod C Ash content of a
5、 peat or organic soil sample sample, for general purposes, is determined byigniting oven dried sample from moisture content determination in a muffle furnace at 440 C.6 40C.1.1.4 Test Method DMethod D Ash content of a peat or organic soil sample sample, for materials used for fuel, is determinedby i
6、gniting oven dried sample from moisture content determination in a muffle furnace at 750 C.6 38C.1.2 This test methodTest Method A should be used for geotechnical and general classification. In addition, the test methodgeneral classification, except for use of the peat as a fuel. Test Method B shoul
7、d be used when peats are being evaluated for useas a fuel.fuel1.3 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.Use Practice D6026 for determining significant digits to report.1.4 This standard does not purport to addres
8、s all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.5 This test method offers a set of instructions for perform
9、ing one or more specific operations. This document cannot replaceeducation or experience and should be used in conjunction with professional judgment. Not all aspects of this test method may beapplicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of
10、 care by which theadequacy of a given professional service must be judged, nor should this document be applied without consideration of a projectsmany unique aspects. The word “Standard” in the title of this document means only that the document has been approved thoughthe ASTM consensus process.2.
11、Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil, Rock, and Contained FluidsD2216 Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by MassD3740 Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil a
12、nd Rock as Used inEngineering Design and ConstructionD4753 Guide for Evaluating, Selecting, and Specifying Balances and Standard Masses for Use in Soil, Rock, and ConstructionMaterials TestingD6026 Practice for Using Significant Digits in Geotechnical Data1 These test methods are under the jurisdict
13、ion ofASTM Committee D18 on Soil and Rock and are the direct responsibility of Subcommittee D18.22 on Soil as a Mediumfor Plant Growth.Current edition approved March 15, 2007June 1, 2013. Published May 2007July 2013. Originally approved in 1971. Last previous edition approved in 2007 asD2974 07.D297
14、4 07a. DOI: 10.1520/D2974-07A.10.1520/D2974-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document
15、is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appro
16、priate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United Stat
17、es1E145 Specification for Gravity-Convection and Forced-Ventilation Ovens3. Terminology3.1 Definitions:3.1.1 For common definitions of terms in this standard, refer to Terminology D653.4. Summary of Test Methods4.1 Test Method AMoisture is determined by drying a peat or organic soil sample at 105C.
18、110 6 5C. The moisture contentis expressed either as a percent of the oven dry mass or of the as-received mass.4.2 Test Method BThis is an alternative moisture method which removes the total moisture in two steps: (1) evaporation ofmoisture in air at room temperature (air-drying), and (2) the subseq
19、uent oven drying of the air-dried sample at 105C. This methodprovides a more stable sample, the air-dried sample, when tests for nitrogen, pH, cation exchange, and the like are to be made.1106 5C. This method is used when the peat is to be used as fuel. The moisture content is expressed as both a pe
20、rcent of the ovendry mass and of the as received mass.4.3 Test Methods C and DAsh content of a peat or organic soil sample is determined by igniting the oven-dried sample fromthe moisture content determination in a muffle furnace at 440C (Method C) or 750C (Method 440 6 40C (Test Method C) or750 6 3
21、8C (Test Method D). The substance remaining after ignition is the ash. The ash content is expressed as a percentage ofthe mass of the oven-dried sample.4.4 Organic matter is determined by subtracting percent ash content from one hundred.5. Significance and Use5.1 This test method can be used to dete
22、rmine the moisture content, ash content, and percent organic matter in soil.5.2 The percent organic matter is important in the following: (1)(1) classifying peat or other organic soil, (2)(2) geotechnicaland general classification purposes, and (3)(3) when peats are being evaluated as a fuelfuel.NOT
23、E 1The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of theequipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objectivetesting/sampling
24、/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliableresults depend on many factors; Practice D3740 provides a means of evaluating some of those factors.6. Apparatus6.1 Oven, meeting the requirements of E145 and
25、 capable of being regulated to a constant temperature of 105110 6 5C.6.2 The temperature of 105 C 110 6 5C is quite critical for organic soils. The oven should be checked for “hot spots” to avoidpossible ignition of the specimen.6.3 Muffle Furnace, capable of producing constant temperatures of 440 C
26、 6 22 C 40C and 750 C 6 38C 38C.6.4 Balance or Scale, a balance or scale for determining the mass of the soil having a minimum capacity of 500 g and meetingthe requirements of StandardGuide D4753 for a balance or scale of 0.01 g readability.6.5 Rubber Sheet, Oil Cloth, or other non-absorbent materia
27、l.6.6 Evaporating Dishes, of high silica or porcelain of not less than 100-mL capacity.6.7 Blender, high-speed.6.7 Aluminum Foil, heavy-duty.6.8 Porcelain Pan, Spoons, and equipment of the like.6.9 Desiccator.7. Sampling and Test Specimens7.1 Place a representative field sample on a rubber sheet, oi
28、l cloth, or equivalent material and mix thoroughly.7.2 Reduce the sample to the quantity required for a test specimen by quartering.7.3 Place the test specimen and the remaining sample in separate waterproof containers.7.4 Work rapidly to prevent moisture loss or perform the operation in a room with
29、 a high humidity.8. Procedure8.1 Moisture Content DeterminationDetermination:8.1.1 Test Method AA:D2974 1328.1.1.1 Record to the nearest 0.01 g the mass of a high silica or porcelain evaporating dish fitted with a heavy-duty aluminumfoil cover. The dish shall have a capacity of not less than 100 mL.
30、8.1.1.2 Following the instruction in sectionSection 7.17 above, place a test specimen of at least 50 g in the container describedin 8.1.1.1. Crush soft lumps with a spoon or spatula. The thickness of peat in the container should not exceed 3 cm.8.1.1.3 Cover immediately with the aluminum foil cover
31、and record the Record the mass to the nearest 0.01 g.8.1.1.4 Dry uncovered for at least 16 h at 105C 110 6 5C or until there is no less than 0.1 % change in mass of the sampleafter further drying periods in excess of 1 h. per hour. Remove from the oven, cover tightly, cool in a desiccator, and recor
32、d themass to the nearest 0.01 g.g keeping exposure to the room atmosphere to a minimum.8.1.2 Calculations for Test Method AA:8.1.2.1 Calculate the moisture content as follows:Moisture Content,%5A 2B! 3100#/A (1)where:A = mass of the as-received test specimen, g, andB = mass of the oven-dried specime
33、n, g.(1) This calculation is used primarily for agriculture, forestry, energy, and horticultural purposes and the result should bereferred to as the moisture content as a percentage of as-received or total mass.8.1.2.1 An alternative calculation isCalculate the moisture content as follows:Moisture C
34、ontent,%5A 2B! 3100#/B (1)where:A = mass of the as-received test specimen, g, andB = mass of the oven-dried specimen, g.(1) This calculation is used primarily for geotechnical purposes general purposes (except when the peat is to be used as a fuel)and the result should be referred to as the moisture
35、 content as a percentage of oven-dried mass.8.1.2.3 Take care to indicate the calculation method used.8.1.3 Test Method BB:8.1.3.1 This test method should be used if pH, nitrogen content, cation exchange capacity, and the like are to be tested.the peatis to be used as a fuel.8.1.3.2 Following the in
36、structions in section 7.1 above, select a 100 to 300 g representative test specimen. Determine the massof this test specimen to the nearest 0.01 g and spread it evenly on a large flat pan. Crush soft lumps with a spoon or spatula andlet the sample come to moisture equilibrium with room air. This wil
37、l require at least 24 h. Stir occasionally during the normalworkday to maintain maximum air exposure of the entire sample. When Continue drying until there is no less than 0.1% changein mass of the sample after further drying periods in excess of 1 h, per hour, then calculate the moisture removed du
38、ring air dryingas a percentage of the as-received mass.8.1.3.3 Grind a representative portion of the air-dried sample for 1 to 2 min in a high-speed blender. Use the ground portionfor moisture, ash, nitrogen, cation exchange capacity tests, and the like.8.1.3.3 Thoroughly mix the air-dried, ground s
39、ample. Weigh to the nearest 0.01 g the equivalent of 50 g of test specimen onan as-received basis. Determine the amount, in grams, of air-dried sample equivalent toair-dried sample and weigh 50 g ofas-received sample, as follows:air-dried sample to theEquivalent Sample Mass,g550.02503M!/100# (3)near
40、estwhere:M = moisture removed in air drying, % (on as received basis).0.01 g.8.1.3.4 Place the sample in a container as described in 8.1.1 and proceed as in Test Method A.8.1.4 Calculations for Test Method BB:8.1.4.1 Calculate the moisture content as follows:Moisture Content,%5502B! 32 (2)Moisture C
41、ontent for Air-Dried Sample,%5AD 2 B! 3100!B (2)where:AD = mass of the air-dried sample, g, andB = mass of the oven-dried sample, g.(1) This calculation gives moisture content of the air dried sample as a percentage of as-receivedoven-dried mass.8.1.4.2 An alternative calculation is as follows:D2974
42、 133Moisture Content,%5502B! 3100#/B (5)(1) This calculation gives moisture content as a percentage of oven-dried mass.8.2 Ash Content DeterminationDetermination:8.2.1 Test Method CC:8.2.1.1 Determine the mass of a covered high-silica or porcelain dish to the nearest 0.01 g.8.2.1.2 Place a part of o
43、r all of the oven-dried test specimen from a moisture determination in the dish and determine the massof the dish and specimen to the nearest 0.01 g.8.2.1.3 Remove the cover and place the dish in a muffle furnace. Gradually bring the temperature in the muffle furnace to 440C 6 22 C 40C and hold unti
44、l the specimen is completely ashed (no change of mass occurs after at least 1 hr.hr period ofheating).8.2.1.4 Cover with the retained aluminum foil cover, cool Cool in a desiccator, and determine the mass to the nearest 0.01 g.gkeeping the exposure to the room atmosphere to a minimum.8.2.1.5 This te
45、st method should be used for geotechnical and general classification purposes.general classification purposes,except the use of peat for fuel.8.2.2 Test Method DD:8.2.2.1 Determine the mass of a covered high-silica or porcelain dish to the nearest 0.01 g.8.2.2.2 Place a part of or all of the oven-dr
46、ied test specimen from a moisture determination in the dish and determine the massof the dish and specimen to the nearest 0.01 g.8.2.2.3 Remove the cover and place the dish in a muffle furnace. Gradually bring the temperature in the muffle furnace to 750C 6 38 C 38C and hold until the specimen is co
47、mpletely ashed (no change in mass of the sample after further drying periodsin excess of 1 h).8.2.2.4 Cover with the retained aluminum foil cover, cool Cool in a desiccator, and determine the mass to the nearest 0.01 g.gkeeping the exposure to the room atmosphere to a minimum.8.2.2.5 This test metho
48、d should be used when peats are being evaluated for use as a fuel.8.2.3 Calculation for Test Methods C and DD:8.2.3.1 Calculate the ash content as follows:Ash Content,%5C 3100!/B (3)where:C = mass of ash, g, andB = oven-dried test specimen, g.8.3 Organic Matter DeterminationDetermination:8.3.1 Calcu
49、lationCalculation:8.3.1.1 Determine the amount of organic matter to the nearest 0.1 % by difference, as follows:Organic matter,%5100.02D (4)where:D = ash content, % (nearest 0.1%).D = ash content, % (nearest 0.1 %).9. ReportReport: Test Data Sheet(s)/Form(s)9.1 Record as a minimum the following general information:9.1.1 Sample/specimen identifying information, such as Project No., Boring No., Sample No., Depth, etc.9.1.2 Any special selection and preparation process, such as removal of gravel or other materials.9.1.
