1、Designation: D5890 18Standard Test Method forSwell Index of Clay Mineral Component of GeosyntheticClay Liners1This standard is issued under the fixed designation D5890; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers an index method that enablesthe evaluation of swelling properties of a clay mineral inreagent wa
3、ter for estimation of its usefulness in geosyntheticclay liners (GCLs). This test method is not applicable for clayswith polymers.1.2 It is adapted from United States Pharmacopeia (USP-NF-XVII) test method for bentonite.1.3 Powdered clay mineral is tested after drying to constantweight at 105 6 5 C;
4、 granular clay mineral should be groundto 100 % passing a 150-m (No. 100) U.S. Standard Sieve witha minimum of 65 % passing a 75-m (No. 200) U.S. StandardSieve. The bentonite passing the 150-m U.S. Standard Sieveis used for testing after drying to constant weight at 105 65 C.1.4 The values stated in
5、 SI units are to be regarded asstandard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicabilit
6、y of regulatory limitations prior to use.Specific precautionary statements are given in Section 8.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International
7、Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD4643 Test Method for Determination of Water Content ofSoil and Rock by Microwave Oven HeatingD4753
8、 Guide for Evaluating, Selecting, and Specifying Bal-ances and Standard Masses for Use in Soil, Rock, andConstruction Materials TestingE1 Specification for ASTM Liquid-in-Glass ThermometersE145 Specification for Gravity-Convection and Forced-Ventilation OvensE691 Practice for Conducting an Interlabo
9、ratory Study toDetermine the Precision of a Test MethodE725 Test Method for Sampling Granular Carriers andGranular Pesticides2.2 United States Pharmacopeia Standard:3USP-NF-XVII Bentonite3. Terminology3.1 Definitions:3.1.1 oven-dried, adjthe condition of a material that hasbeen heated under prescrib
10、ed conditions of temperature andhumidity until there is no further significant change in its mass.4. Significance and Use4.1 Clay mineral is a major functional component of GCLsystems that reduces the hydraulic conductivity of industrial,waste, or ground water through the liner.4.2 Clay mineral qual
11、ity can vary significantly and affect thehydraulic conductivity of the GCL composite. This test methodevaluates a significant property of clay mineral that relates toperformance.5. Atmosphere Conditions5.1 Atmospheric ConditionsThe atmospheric conditionsof the laboratory performing swell index of cl
12、ay mineral1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.04 on Geosyn-thetic Clay Liners.Current edition approved Aug. 1, 2018. Published August 2018. Originallyapproved in 1995. Last previous edition approved in
13、 2011 as D5890 11. DOI:10.1520/D5890-18.2For 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 Summary page onthe ASTM website.3Available from U.S.
14、Pharmacopeia (USP), 12601 Twinbrook Pkwy., Rockville,MD 20852.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization establi
15、shed in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1component of geosynthetic clay liners shall be: relative humid-ity of 70 % and temperature of 23 6 4 C.6. A
16、pparatus6.1 Mortar and Pestle or Laboratory Hammer Mill, forgrinding clay mineral to required particle sizing.6.2 U.S. Standard Sieve, 150 m (No. 100), 75 m (No.200).6.3 Drying Oven, thermostatically controlled, preferablyforced-draft type, meeting requirements of Specification E145,and capable of m
17、aintaining a uniform temperature of 105 65 C throughout the drying chamber.6.4 Desiccator, of suitable size, containing indicator silicagel. It is preferable to use desiccant which changes color toindicate when it needs reconstitution.6.5 Laboratory Balance, 100-g capacity, 60.01-g accuracyand preci
18、sion.6.6 Weighing Paper, or small weighing dish.6.7 Glass Cylinder, graduated TC (to contain), Class Avolumetrically calibrated, with 1-mL subdivisions and groundglass stopper, high form with approximately 180-mm heightfrom inside base to 100-mL mark.6.8 Wash Bottle, for dispensing reagent water.6.9
19、 Spatula, flat-blade, to dispense clay mineral powder intocylinder; vibrating spatula should not be used, since thedelivery quantity may not be adequately controlled.6.10 Mechanical Ten-Minute Timer.6.11 ASTM Calibration Immersion Thermometer, (Specifi-cation E1).6.12 Microwave OvenA microwave oven,
20、 preferably witha vented chamber, is suitable. The required size and powerrating of the oven is dependent on its intended use. Ovens withvariable power controls and input power ratings of about700 W have been found to be adequate for this use. Variablepower controls are important and reduce the pote
21、ntial foroverheating the test specimen.NOTE 1Microwave ovens equipped with built-in scales and computercontrols have been developed for use in drying soils. Their use iscompatible with this test method.6.13 BalancesAll balances must meet the requirements ofGuide D4753 and this section. A Class GP1 b
22、alance of 0.01-greadability is required for samples having a mass of up to 200 g(excluding mass of sample container).6.14 Sample ContainersSuitable containers made of ma-terial resistant to corrosion and change in mass upon repeatedheating, cooling, exposure to materials of varying pH, andcleaning.
23、Microwave sample containers should be microwavesafe.6.15 Container Handling ApparatusGloves, tongs, orsuitable holder for moving and handling hot containers afterdrying.7. Reagents7.1 Purity of ReagentsUnless otherwise indicated, refer-ences to water shall be understood to mean reagent waterconformi
24、ng to Specification D1193, Type I, II, or III (see TableX1.1). Such water is best prepared by distillation or the passageof tap water through an ion exchange resin.8. Hazards8.1 Handle hot containers with a container holder.8.2 Safety precautions supplied by the manufacturer of themicrowave/oven sho
25、uld be observed.8.3 Do not use metallic containers in a microwave oven (ifused).9. Samples, Specimens, and Test Units9.1 For testing from a large bulk (for example, 1 t) beforethe GCL production, carry out sampling in accordance withTest Method E725.10. Procedure10.1 Grind the clay mineral sample to
26、 100 % passing a150-m (No. 100) U.S. Standard Sieve and a minimum of 65 %passing a 75-m (No. 200) U.S. Standard Sieve with a mortarand pestle or laboratory hammer mill, as required. The totalmass of the test specimen shall be a minimum of 100 g.10.2 The container to be used for drying should be oven
27、dried thoroughly and subsequently placed into a desiccatoruntil ready for use so that the tare weight of the container willbe recorded.10.3 Determine and record the tare of the specimen con-tainer.10.4 Place the test specimen in the individual container.Determine the mass of the container and clay s
28、pecimen asdelivered, using a balance selected on the basis of the samplemass. Record the value of the clay specimen.NOTE 2To prevent mixing of samples and yielding of incorrectresults, all containers should be numbered and the container numbers shallbe recorded on the laboratory data sheets.10.5 Pla
29、ce the container with the clay specimen in thedrying oven. Dry the clay specimen to a constant mass.Maintain the drying oven at 105 6 5 C. The time required toobtain constant mass will vary depending on the type ofmaterial, oven type and capacity, and other factors.NOTE 3In most cases, drying a test
30、 sample overnight (about 12 to16 h) is sufficient for conventional ovens. In cases where there is doubtconcerning the adequacy of drying, drying should be continued until thechange in mass after two successive periods (greater than 1 h) of dryingis less than 0.1 %. In this case, it should be verifie
31、d that excessive dryingdoes not influence the swelling performance of the clay. This can be doneby comparing the swelling values after the first drying period (about 12 to16 h) and the swelling values of bentonite being dried for a longer timeperiod.NOTE 4If a microwave oven is used to dry the test
32、specimen(s), theuser of this test method should follow the drying procedures as stated inTest Method D4643. It is further recommended to run a comparison testbetween the microwave oven and the drying oven to demonstrate that themicrowave oven gives similar values as the drying oven and that excessiv
33、edrying does not change the swelling performance of the clay.NOTE 5Since some dry materials may absorb moisture from moistsamples, dried samples should be removed before placing moist samplesin the same oven. However, this would not be applicable if the previouslydried specimens will remain in the d
34、rying oven for an additional timeperiod of about 16 h.D5890 18210.6 After the material has dried to constant mass, removethe container from the oven (and replace the lid if used). Allowthe material and container to cool to room temperature in adesiccation unit or until the container can be handled c
35、omfort-ably with bare hands and the operation of the balance will notbe affected by convection currents or its being heated, or both.Determine the mass of the container and oven-dried materialusing the same balance as used previously. Subtract the tare ofthe container from the mass of the sample to
36、determine thesamples constant dry mass. Record this value.10.7 Weigh 2.00 6 0.01 g of dried and finely ground claymineral onto a weighing paper.10.8 Add 90 mL reagent water to the clean 100-mL gradu-ated cylinder.10.9 Remove not more than a 0.1-g increment of claymineral from weighing dish or paper
37、and carefully dust it overthe entire surface of water in the graduated cylinder over aperiod of approximately 30 s. Do not use a funnel that mayconcentrate the clay mineral in a poorly hydrated agglomerate.Allow the clay mineral to wet, hydrate, and settle to the bottomof the graduated cylinder for
38、a minimum period of 10 min.10.10 Add additional increments of the clay mineral powderin periods of 10 min, allowing the clay mineral to swell withoutair being trapped in between, following the details in 10.9, untilthe entire 2.00-g sample has been added.10.11 After the final increment has settled,
39、carefully rinseany adhering particles from the sides of the cylinder into thewater column, raising the water volume to the 100-mL mark.10.12 Place the glass stopper on the cylinder and allow it tostand undisturbed for a minimum of 16 h from the lastincremental addition. After 2 h, inspect the hydrat
40、ing claymineral column for trapped air or water separation in thecolumn. If present, gently tip the cylinder at a 45 angle androll slowly to homogenize the settled clay mineral mass. Allowthe graduated cylinder with the hydrating clay mineral toremain undisturbed for a minimum of 16 h before recordi
41、ng thevolume of the hydrated clay mass and its temperature.10.13 After the minimum 16-h hydration period from thelast increment addition, record the volume level in millilitres(mL) at the top of the settled clay mineral to the nearest0.5 mL. Observe the distinct change in appearance at the uppersurf
42、ace of the settled clay mineral.Any low-density flocculatedmaterial (sometimes lighter in coloration to white) shall beignored for this measurement. Record the observed volume ofhydrated clay mineral to the nearest 0.5 mL.10.14 If a recognizable swelling still occurs after the mini-mum hydration per
43、iod from the last increment addition (morethan 10 % of the previous reading in a 4-h period), continuerecording the volume of the hydrated clay mass and itstemperature to a maximum of 48 h after the last incrementaddition.10.15 Carefully immerse the thermometer and measure thetemperature of the slur
44、ry. Record the temperature of thehydrated clay mineral to 60.5 C.11. Report11.1 Report the following information:11.1.1 Source of clay mineral, including sample identifica-tion or lot number,11.1.2 Method of sampling used,11.1.3 ASTM standard test method number used to performthe test,11.1.4 Any mod
45、ifications to the test method or unusualobservations which may affect the test results, and11.1.5 Swell index as mL/2 g to the nearest 0.5 mL after theminimum 16-h hydration period from the last clay incrementaddition and, if applicable, to the maximum recorded hydrationperiod from the last clay inc
46、rement addition.12. Precision and Bias12.1 Interlaboratory Test ProgramAn interlaboratorystudy of the test method was run in 1999. The design of theexperiment was similar to that of Practice E691. Sevendifferent clay mineral samples were distributed to ten labora-tories. Three sets of test results w
47、ere generated for each sampleby each of the laboratories.12.2 Test ResultsThe precision information is given inTable 1. The average swell index values ranged from 20 to 36for the seven clay mineral samples tested. However, since thestatistics were not related to the magnitude of the test result, the
48、precision values have been presented in terms of coefficients ofvariation, CV %.12.3 BiasThe procedure in Test Method D5890 for mea-suring the swell index of clay mineral component of geosyn-thetic clay liners has no bias because the values of swell indexcan be defined only in terms of this test met
49、hod.13. Keywords13.1 bentonite; clay; geosynthetic clay liner; microwave;oven drying; swell; swell indexTABLE 1 Test ResultsStatistic ILS RangeWithin-laboratory repeatability limit, CV % r 2to5%Between-laboratory reproducibility limit, CV % R 7to22%95 % confidence limitWithin-laboratory repeatability, 2.8 CV % r6to14%95 % confidence limitBetween-laboratory reproducibility, 2.8 CV % R20 to 61 %D5890 183APPENDIXES(Nonmandatory Information)X1. ADDITIONAL REAGENT INFORMATIONX1.1 See Table X1.1.X2. CHECKLISTTABLE X1.1 Additional Reagent InformationType I
