1、Designation: D6072/D6072M 18Standard Practice forObtaining Samples of Geosynthetic Clay Liners1This standard is issued under the fixed designation D6072/D6072M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the year of last revis
2、ion. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers procedures for sampling geosyn-thetic clay liners (GCLs) for the purpose of laboratory testing.These proced
3、ures are designed to ensure that representativesamples are obtained and properly packaged for submittal to atesting laboratory.1.2 The procedures in this practice may be applied to eithersamples of unhydrated GCLs obtained at the project site priorto installation (or at the production facility, prio
4、r to shipment tothe project site) or samples exhumed from a project site afterinstallation.1.3 It is assumed that the number of samples to be obtainedhas already been determined in the project specification,standard test method, or by prior agreement between thepurchaser and seller. This practice co
5、vers only the methods forobtaining a pre-arranged number of samples and does notdescribe methods for obtaining individual specimens from thesample.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact e
6、quivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in nonconformancewith the standard.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
7、 of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in t
8、he Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D4220/D4220M Practices for Preserving and TransportingSoil SamplesD4354 Pr
9、actice for Sampling of Geosynthetics and RolledErosion Control Products (RECPs) for TestingD4439 Terminology for GeosyntheticsD5888 Guide for Storage and Handling of GeosyntheticClay Liners3. Terminology3.1 Definitions:3.1.1 geosynthetic clay liner (GCL), na manufacturedhydraulic barrier consisting
10、of clay bonded to a layer or layersof geosynthetics.3.1.2 sample, na portion of a material which is taken fortesting or for record purposes (see Practice D4354).3.1.3 specimen, na specific portion of a material orlaboratory sample upon which a test is performed or which istaken for that purpose (see
11、 Practice D4354).3.2 For definitions of other geosynthetic terms used in thispractice, refer to Terminology D4439.4. Significance and Use4.1 This practice provides a procedure by which samples ofGCL should be obtained for laboratory testing. The practiceapplies to materials obtained prior to install
12、ation (either at a jobsite or at a production facility) or exhumed material afterinstallation.4.2 Only GCL samples obtained in accordance with 5.1 ofthis practice will be considered representative of the actualmanufactured GCL for quality assurance/quality control (QA/QC) purposes.4.3 The quantity o
13、f GCL received by the laboratory shouldbe sufficient for the preparation of several representative testspecimens for the standardized physical, hydraulic, and me-chanical tests to be performed on the GCLs.1This practice is under the jurisdiction of ASTM Committee D35 on Geosyn-thetics and is the dir
14、ect responsibility of Subcommittee D35.04 on GeosyntheticClay Liners.Current edition approved June 1, 2018. Published June 2018. Originallyapproved in 1996. Last previous edition approved in 2015 as D6072/D6072M 09(2015). DOI: 10.1520/D6072_D6072M-18.2For referenced ASTM standards, visit the ASTM we
15、bsite, 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United Sta
16、tesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Tr
17、ade (TBT) Committee.14.4 The procedures in this practice should be used by plantand field personnel for obtaining GCL samples for laboratorytesting.5. Procedure5.1 Obtaining Samples Prior to Installation:5.1.1 In accordance with the project specifications or withPractice D4354, divide the shipment o
18、r other given quantity ofGCL into lots, and select lot and laboratory samples. This willusually involve the selection of a certain number of finishedGCL rolls from which samples will be cut.5.1.2 Affix on the packaging of the GCL rolls to be sampledadhesive labels or other markings which clearly ide
19、ntify thatthe roll is to be sampled.5.1.3 Record the label information from each roll to besampled for future incorporation into within the qualityassurance/quality control (QA/QC) documentation for theGCL.5.1.4 Segregate the rolls identified for sampling. Refer toGuide D5888 for the proper equipmen
20、t and techniques forhandling the GCL rolls.5.1.5 Inspect the packaging of the selected GCL rolls fordamage. Describe and record the damage, if any.5.1.6 Remove the outer packaging from the GCL as care-fully as possible, taking precautions not to damage the GCLand to preserve the packaging as much as
21、 possible for re-useafter sampling is completed.5.1.7 Obtain samples from the selected GCL rolls prior todeployment. If cut on a surface, the surface on which the GCLis cut shall be dry, clean, smooth, hard, and free of irregularitiesand potential contaminants. Samples shall be obtained bycutting ac
22、ross the full width of the roll, perpendicular to theedges. Samples shall be cut with a sharp utility knife or otherimplement capable of making a clean, straight cut through allcomponents of the GCL. When cutting a sample from a roll, donot sample the first 1.0 m 3.0 ft or the last 1.0 m 3.0 ft ofth
23、e roll. For large-diameter rolls, the 1.0-m 3.0-ft outer scraplength may not be enough. As such, the samples shall notinclude the outer layer of the roll.NOTE 1At the discretion of the engineer, shorter or narrower samples,or both, may be obtained provided that the packaging procedures in thispracti
24、ce are followed.5.1.8 A unique sample number shall be written on thesample. Additional markings should be made on the sample toidentify the machine direction and the top/bottom sides of theGCL.5.1.9 The GCL sample shall then be manually rolled arounda core at least 75 mm in diameter, in the same dir
25、ection as thecut. Care should be taken to wind the GCL without slack. Widestrapping tape (50 mm) shall then be wound around the samplein at least two places to secure the loose end. Bentonite lossfrom the sample may be minimized by applying the tapearound the roll ends.5.1.10 At least two layers of
26、plastic sheeting shall be used towrap the GCL sample roll for shipment to the laboratory, so asto minimize GCL sample disturbance or changes in moisturecontent. A thin cellophane material may be used for the innerwrapping, provided it is wound securely and repeatedly aroundthe rolled sample. The out
27、er sheeting shall be at least 0.15 mm6 mils in thickness and shall be wrapped to minimize theamount of GCL shifting within the wrapping.5.1.11 To ensure proper sample chain-of-custody tracking,all shipping documents shall indicate the sample number,project name and contact, and laboratory name and c
28、ontact.5.1.12 If an additional sample from the same GCL roll isrequired for testing, 5.1.6 5.1.10 of this practice may berepeated on the exposed end of the roll until a sufficient amountof GCL is obtained.NOTE 2Additional material cut from the same roll is still consideredpart of the same sample, an
29、d therefore should not be designated anydifferently than those samples previously obtained from the same roll.5.1.13 Samples should be transmitted to the laboratory in amanner that minimizes the amount of elapsed time, samplehandling, and disturbances (such as moisture, vibration,impact, etc.) that
30、could occur in transit. Expedited delivery willhelp to ensure that moisture content changes are minimized.NOTE 3These packaging procedures were developed under theassumption that the area from which specimens are obtained is at least75 mm from the edges of the sample.5.2 Exhuming Samples After Insta
31、llation:5.2.1 There are two methods for exhuming GCL samples.Method A is the suggested method for multi-component GCLsor GCLs covered with a geomembrane. Method B is thesuggested method when there is no multi-component GCL noris the GCL covered with a geomembrane, although Method Acan be used in cas
32、es where larger samples are required.5.2.2 Method A Hand Cutting Method:5.2.2.1 Using a small backhoe or other piece of constructionequipment, carefully excavate a hole at the desired locationdown to within hand shoveling distance of approximately150 mm 6 in. of the GCL. Once cover removal begins,ma
33、chinery should not be placed in the area to be exhumed. Tominimize stress on GCL, within 150 mm 6 in. of the GCL,the overlying soil should be removed by hand and anyoverlying geosynthetics shall be cut by hand. Measure thedepth of the cover soil, as well as the inclination and directionof inclinatio
34、n; for example, south, east, west, north.NOTE 4Once the overlying soil is removed, evaporation of water inthe GCL may occur. Consequently, the GCL should be removed no morethan 30 min from the time the overlying soil is removed. When a GCL isoverlain by a geomembrane, the geomembrane should remain i
35、n placeuntil the GCL is to be sampled. If heating of the geomembrane by solarradiation is a concern during this period, a white fabric or white plasticsheet should be draped over the geomembrane to reflect solar radiation.5.2.2.2 The sample area shall be large enough such thatspecimens subsequently
36、cut from the removed sample in thelaboratory for testing are no closer than 75 mm from any edge.The sample also must not be cut too close to the side of theexcavation so that the geomembrane and GCL may be repairedor patched as recommended by the manufacturers.5.2.2.3 If the GCL is overlain with a g
37、eomembrane, first thegeomembrane shall be cut over an area larger than thesubsequent GCL sample area and removed prior to cutting theGCL. GCL samples shall be cut with a sharp utility knife orother implement capable of making a clean, straight cutthrough all the components of the GCL.D6072/D6072M 18
38、25.2.2.4 The sample width and length dimensions shall bemeasured and recorded.5.2.2.5 To minimize the potential for bending or distortingthe GCL, the sample shall be kept flat at all times duringremoval and placed upon a nonporous rigid plate. This can beaccomplished by cutting a notch into the subg
39、rade adjacent tothe GCL, placing the rigid plate into the notch adjacent to theGCL sample, and either sliding the GCL onto the plate orsliding the plate below the GCL (see Fig. 1).5.2.2.6 To minimize changes in moisture content, at leasttwo layers of plastic sheeting shall be used to wrap the GCLsam
40、ple and plate for shipment to the laboratory. A thincellophane material may be used for the inner wrapping,provided the cellophane is wound securely and repeatedlyaround the sample and plate. The outer sheeting shall be at least0.1 mm 4 mils in thickness and shall be wrapped tightlyenough to minimiz
41、e the amount of GCL shifting within thewrapping.5.2.2.7 Unique sample identification shall be marked on thewrapped sample.5.2.2.8 If requested and practical, a confining pressure canbe applied upon the GCL sample. This can be accomplishedeither by placing a second rigid plate over the GCL prior towr
42、apping and then placing dead weights over the sample, or byplacing the sample in a container and then carefully placing asufficient amount of soil over the sample.5.2.2.9 Sample soils immediately adjacent to the GCL perPractices D4220/D4220M.5.2.2.10 If required, repair or patch (or both) the geosyn
43、-thetics in the excavation as recommended by the manufacturersand backfill the entire excavation according to the protocolagreed to by the parties involved.5.2.2.11 To ensure proper sample chain-of-custody tracking,all shipping documents shall indicate the sample number,project name and contact, and
44、 laboratory name and contact.5.2.2.12 Samples should be transmitted to the laboratory ina manner that minimizes the amount of elapsed time, samplehandling, and disturbances (such as moisture loss, distortion,impact, etc.) that could occur in transit. Expedited delivery willhelp to ensure that moistu
45、re content changes are minimized.5.2.2.13 Samples should be stored and handled by thelaboratory in a manner that minimizes the amount of elapsedtime, sample handling, and disturbances (such as moisture loss,distortion, impact, etc.) that could occur prior to testing.5.2.3 Method B Coring Method:5.2.
46、3.1 Using a small backhoe or other piece of constructionequipment, carefully excavate a hole at the desired locationdown to within hand shoveling distance of approximately15 cm 6 in. of the GCL. Carefully remove the remaining soilby hand to within 25 mm 1 in. of the top of the GCL.5.2.3.2 Advance a
47、hand auger with a 150-mm 6-in.diameter, end-sharpened, thin-wall sampling tube (see Fig.2(a) into the cover soil to the top of the GCL.NOTE 5ParAide Turf Mender Model #1004 with ParAide Tube BladeModel #1010 has been found satisfactory for this purpose.5.2.3.3 After advancing the auger to the surfac
48、e of the GCL,a utility knife should be used to pre-cut the GCL around the150-mm 6-in. diameter inner perimeter of the tube. Thenadvance the auger through the pre-cut GCL and approximately25 mm 1 in. beneath the GCL.5.2.3.4 Withdraw the sampler from the soil formation ascarefully as possible in order
49、 to minimize disturbance of thesample. The tube can be slowly rotated to shear the material atthe end of the tube, and to relieve water or suction pressures,or both, and improve recovery. Retrieve the auger with itssoil/GCL/soil sample. Remove the thin-wall sampling tube atthe end of the auger and immediately seal both sample ends,ensuring that the sample has no way of moving about in thetube.NOTE 6If soil is lost and not flush with either end of the tube, thenspacers or appropriate packing materials should be inserted prior tosealing the tube
