1、Designation: D7272 06 (Reapproved 2018)Standard Test Method forDetermining the Integrity of Seams Used in JoiningGeomembranes by Premanufactured Taped Methods1This standard is issued under the fixed designation D7272; the number immediately following the designation indicates the year oforiginal ado
2、ption or, in the case of revision, the 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. Scope1.1 This test method describes destructive quality controland/or quality as
3、surance tests to determine the integrity ofseams produced using taped seaming methods. This testmethod presents the procedures used for determining thequality of taped seams subjected to both peel and shear tests.These test procedures are intended for nonreinforced andreinforced geomembranes.1.2 The
4、 types of tape seaming techniques used to constructgeomembrane seams include the following:1.2.1 Inseam TapeThis technique requires the membraneto be overlapped a minimum distance. The top sheet is foldedback and both the bottom sheet and the top sheet are primedwith an adhesive primer. The primer i
5、s allowed to flash off. Thetape adhesive is applied to the bottom sheet so that a minimumof the tape will extend out from under the top sheet when laidover the tape. The top sheet is allowed to lay flat over the tapeand the release paper is removed by pulling it at a 45 to 90degree angle, keeping th
6、e release paper flat to the surface of thebottom sheet. The seam area is then rolled with a silicone-sleeved roller.1.2.2 Cover Strip TapeThis technique requires the mem-brane to be overlapped a minimum distance.An area either sideof the seam edge is primed. The primer is allowed to flash off.The co
7、ver strip is applied with the adhesive side down,centered over the top sheet edge while removing the releasepaper as it proceeds along centered over the edge of the topsheet. The cover strip is then rolled with a silicone-sleevedroller.1.3 For nondestructive test methods, see Practice D4437/D4437M.1
8、.4 This test method is applicable for seaming processesthat use tape adhesive as a seaming mechanism.1.5 Subsequent decisions as to seam acceptance criteria aremade according to the site-specific contract plans,specifications, and contractor quality control/contractor qualityassurance (CQC/CQA) docu
9、ments.1.6 In case of a material-specific test method, this testmethod shall take precedence.1.7 Hazardous MaterialsAlways consult the proper mate-rial safety data sheets for any hazardous material used for theproper ventilation and protection. The use of the oven in thesetest methods, in this practi
10、ce, may accelerate fume productionfrom the test specimen.1.8 The values stated in both inch-pound and SI units are tobe regarded separately as the standard. Values in parenthesesare for information only.1.9 This standard does not purport to address all of thesafety concerns, if any, associated with
11、its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.10 This international standard was developed in accor-dance with internationally recognized pr
12、inciples on standard-ization established in the 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:2D413 Test Methods for Rubber
13、PropertyAdhesion to Flex-ible SubstrateD638 Test Method for Tensile Properties of PlasticsD653 Terminology Relating to Soil, Rock, and ContainedFluidsD882 Test Method for Tensile Properties of Thin PlasticSheetingD4437/D4437M Practice for Nondestructive Testing (NDT)for Determining the Integrity of
14、Seams Used in JoiningFlexible Polymeric Sheet Geomembranes1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.10 on Geomem-branes.Current edition approved Feb. 1, 2018. Published February 2018. Originallyapproved 2006
15、. Last previous version approved 2011 as D7272 06 (2011). DOI:10.1520/D7272-06R18.2For 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 pag
16、e onthe ASTM website.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 established in the Decision on Principles for th
17、eDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1D4439 Terminology for GeosyntheticsD5199 Test Method for Measuring the Nominal Thicknessof GeosyntheticsD5994/D5994M Test Method for Measuring Core
18、Thicknessof Textured Geomembranes3. Terminology3.1 DefinitionsFor definitions of other geosyntheticsterms used in this method, refer to Terminology D4439. Fordefinitions of soil terms, refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 cover strip adhesive, nsolid str
19、ip of prefabricated ormanufactured adhesive, factory laminated to layer of polymersheet material factory laminated to a release paper, used to jointwo polymer sheets.3.2.2 cover strip adhesive seam, nadhesive-based lami-nated tape placed over two overlapping polymer sheet materi-als forming a surfac
20、e bond.3.2.3 tape adhesive, nsolid strip of prefabricated or manu-factured adhesive, factory laminated to a release paper, used tojoin two polymer sheets.3.2.4 tape adhesive seam, nadhesive-based tape placedbetween two polymer sheet materials forming a surface bond.4. Significance and Use4.1 Signifi
21、canceWith the increased use of geomembranesas a barrier material to restrict liquid migration from onelocation to another, a need has been created for a standard testmethod to evaluate the quality of geomembrane seams pro-duced by tape methods. In the case of geomembranes, it hasbecome evident that
22、geomembrane seams can exhibit separa-tion in the field under certain conditions. This is an index-typetest method used for quality assurance and quality controlpurposes; it is also intended to provide the quality engineerwith sufficient seam peel and shear data to evaluate seamquality.4.2 UseRecordi
23、ng and reporting data, such as separationthat occurs during the peel test and elongation during the sheartest, will allow the quality assurance engineer to take measuresnecessary to ensure the repair of inferior seams duringconstruction, and therefore, minimize the potential for seamseparation while
24、 in service. The acceptable value of adhesionmeasured will, of course, vary from product to product as aresult of different formulations and types of products.However, once a product is established, minimum values ofseparation force can be determined and agreed to by producerand consumer, and both c
25、an monitor the installation to ensuremaintenance of the agreed-upon minimum value.5. Apparatus5.1 Tensile instrumentation shall meet the requirementsoutlined in Test Method D638 or D882.5.2 A testing machine of the constant-rate-of-crosshead-movement type comprising essentially of the following:5.2.
26、1 Fixed MemberA fixed or essentially stationarymember carrying one grip.5.2.2 Movable MemberA movable member carrying asecond grip.5.2.3 GripsGrips for holding the test specimen betweenthe fixed member and the movable member and minimizesboth slippage and uneven stress distribution. The grips shall
27、beself-aligning so that they shall be attached to the fixed andmovable member, respectively, in such a manner that they willmove freely into alignment as soon as any load is applied, sothat the long axis of the test specimen will coincide with thedirection of the applied pull through the center line
28、 of the gripassembly. Grip faces shall be 25 mm (1 in.) wide and aminimum of 25 mm (1 in.) in length. Smooth surfaces, fineserrated, or coarse serrated grip faces, use the grips that haveall been found to be suitable for testing, depending on the typeof geomembrane seams that are being tested.NOTE 1
29、Grips lined with thin rubber, crocus-cloth, or pressure-sensitive tape as well as file-faced or serrated grips have been successfullyused for many materials. The choice of grip surface will depend on thematerial tested, thickness, etc.5.2.4 Drive MechanismA drive mechanism for impartingto the movabl
30、e member in uniform, controlled velocity withrespect to the stationary member. Unless otherwise specified inthe material specification, the mechanism shall be capable ofand adjusted so that the movable member shall have a uniformspeed of 50 mm/min (2 in./min), 300 mm/min (12 in./min), and500 mm/min
31、(20 in./min).5.2.5 Load IndicatorA suitable load-indicating mecha-nism capable of showing the total tensile load carried by thetest specimen when held by the grips. This mechanism shall beessentially free of inertia lag at the specified rate of testing andshall indicate the load with an accuracy of
32、61 % of theindicated value or better.5.2.6 Extension Indicator (Extensometer) (if Employed)Asuitable instrument shall be used for determining the distancebetween two designated points within the gage length of thetest specimen as the specimen is stretched and shall conform torequirements specified i
33、n Test Method D638.6. Sampling and Specimen Preparation6.1 Trial Seam SampleA representative seam from eachseaming crew, fabricated from the same sheet material andusing the seaming methods as those recommended by thegeomembrane fabricator manufacturer, shall be used for thismethod.6.1.1 Destructive
34、 Seam SampleAlternatively, cut a portionof the fabricated seam from the installed liner or a daily testseam sample in accordance with the project specifications. It isrecommended that the cutout sample be 0.3 m (1 ft) wide and0.45 m (1.5 ft) in length with the seam centered in the middleof the seam.
35、6.1.2 Specimen PreparationFive specimens shall be cutfrom the submittal sample for each the peel and shear test. Thespecimens for the peel test shall be cut using a calibrated die,25 6 3 mm (nominal 1 6 0.125 in.) wide by 150 6 3mm(nominal 6 6 0.125 in.) long. The specimens for the shear testshall b
36、e die cut using a calibrated die, 25 6 3 mm (nominal 16 0.125 in.) wide by 2 in. greater than the width of the seam.Specimens shall be such that the die is centered over theD7272 06 (2018)2sample seam, perpendicular to the centerline of the seam. Peeland shear specimens shall be cut as shown in Fig.
37、 1.6.1.3 ConditioningSamples should be conditioned for24 h in a standard laboratory environment that conforms to therequirements for testing geosynthetics as stated in TerminologyD4439. Long sample conditioning times typically are notpossible for most applications that require daily seam testing.Pri
38、or to testing, samples should be conditioned for a minimumof1hat216 2 C and a relative humidity between 50 and70 %.NOTE 2Some adhesives may build up on the die. Dies need to beinspected and cleaned periodically. A nonreactive release agent may beused on the die to reduce adhesive buildup, but type a
39、nd frequency of usemust be documented in test report.7. Destructive Test Methods7.1 Peel TestingSubject five specimens to the 180 “T-peel” test (see Fig. 2). Maintaining the specimen in a horizontalposition throughout the test is not required. Fully grip the testspecimen across the width of the spec
40、imen. Grip the peelspecimen by securing grips 13 mm (12 in.) on each side of thestart of the seam bond. Apply a constant machine crossheadspeed of 500 mm (20 in.)/min. The test is complete when thespecimen ruptures. The seam samples shall be tested inaccordance with Test Methods D413, Method A. The
41、indi-vidual specimens shall be 25 6 3mm(16 0.125 in.) wide andshall be cut with a standard calibrated die. The die shall becentered over the sample seam perpendicular to the centerlineof the seam. The grips shall be positioned 25 mm (1 in.) apartwith no more than 13.5 mm (0.5 in.) on either side of
42、the startof the seam bond (seam bond centered between the grip edges).The grip surfaces shall be acceptable for the testing of thespecific test material to prevent pullout. Grips shall be self-aligning so that the axis of the test specimen will coincide withthe direction of the applied load through
43、the centerline of thegrip assembly. The samples shall be inserted so that they arecentered and under no initial stress and fully supported acrossthe width of the seam. The seam overlap shall be as fabricated.The specimens shall be pulled to rupture.7.2 Shear TestingSubject five specimens to the shea
44、r test(see Fig. 2). Fully support the test specimen within the gripsacross the width of the specimen. The seam samples shall betested in accordance with Test Method D882. The samplesshall be 25 mm (1 in.) wide by 50 mm (2 in.) greater that thewidth of the seam. The cut shall be centered over the sea
45、m,perpendicular to the centerline of the seam. Grip separationshall be 50 mm (2 in.) plus the width of the seam. The samplesshall be tested at a crosshead speed of 500 mm (20 in.)/min.The grip surfaces shall be acceptable for the testing of theFIG. 1 Seam SampleD7272 06 (2018)3specific material to p
46、revent pullout. Grips shall be self-aligningso that the axis of the test specimen will coincide with thedirection of the applied load through the centerline of the gripassembly. The seam overlap shall be as fabricated. Fullysupport the test specimen within the grips across the width ofthe specimen.
47、The specimens shall be pulled to rupture or aspecified percent strain (that is, 50 %, 100 %, 200 %).NOTE 3Both peel and shear tests for fPP, LLDPE, VLDPE, EPDM,and PVC geomembranes have been tested routinely at both 2 and20 in. min. When conducting seam peel or shear testing for quality controlor qu
48、ality assurance purposes, or both, it may be necessary to select themanufacturers recommended testing speed. In the absence of explicittesting speed requirements, follow those recommended in 7.1 and 7.2.8. Calculations and Observations8.1 Estimate of Seam Peel SeparationVisually estimatethe seam sep
49、aration demonstrated prior to rupture for peelspecimens. The estimate shall be based upon the proportion oflinear length of separated bond in the direction of the test, tothe length of original bonding to the nearest 25 %.8.2 Rupture Mode SelectionDetermine the locus of breakfor both the peel and shear specimens as shown in Figs. 3 and4. The locus of break for shear specimens that do not ruptureprior to test end shall be interpreted as occurring in themembrane that exhibits yielding.8.3 Shear Percent ElongationCalculate the percent
