1、Designation: D7408 12Standard Specification forNon Reinforced PVC (Polyvinyl Chloride) GeomembraneSeams1This standard is issued under the fixed designation D7408; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. 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 specification covers the minimum values for seamsfabricated into unreinforced PVC geomembranes in factoryand field applic
3、ations.1.2 This specification covers PVC Geomembranes in thick-ness of .25 through 1.52 mm (0.010 through 0.060 in.)1.3 In addition to structural characteristics, the specifiershall evaluate other characteristics beyond the scope of thisspecification that affect the final choice of construction. The
4、seinclude, but are not limited to, functional, legal, insurance andeconomic considerations.1.4 This specification is not intended to exclude products orsystems not covered by the referenced documents.1.5 The values stated in inch-pound units are to be regardedas standard. The values given in parenth
5、eses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.6 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
6、safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D638 Test Method for Tensile Properties of PlasticsD882 Test Method for Tensile Properties of Thin PlasticSheetingD4439 Terminology for GeosyntheticsD7176 Sp
7、ecification for Non-Reinforced Polyvinyl Chloride(PVC) Geomembranes Used in Buried Applications3. Terminology3.1 Definitions:3.1.1 chemical fusion seams, nuse of a chemical agent todissolve the surface of the geomembrane for bonding.3.1.2 adhesive or bodied solvent, nthese seams are typi-cally produ
8、ced by applying an adhesive to both sides of thesheet to be bonded and then pressure is applied to the top sheetwith the bottom sheet supported by flat a firm surface3.1.3 thermal fusion, n also known as hot air or hotwedge, this technique introduces high-temperature air or gas ora hot wedge between
9、 two geomembrane surfaces to facilitatemelting. Pressure is applied to the top and/or bottom sheets ofthe geomembrane, forcing together the two surfaces to form acontinuous bond.3.1.3.1 DiscussionSome seams of this kind are made withdual bond tracks separated by a non-bonded gap. These seamsare refe
10、rred to as dual track seams or double-track seams3.1.4 hot air or knife, n this technique melts the twogeomembrane surfaces to be seamed by running a hot metalwedge or hot air between them. Pressure is applied to the topor bottom geomembrane, or both, to form a continuous bond.These seams are usuall
11、y produced with a combination of ahand held heat gun or hand held hot wedge along with a handroller.3.2 For definitions of other terms, see Terminology D4439.4. Classification4.1 Types of seams covered in this specification:4.1.1 Chemical Fusion,4.1.2 Adhesive or Bodied Solvent,4.1.3 Dielectric, and
12、4.1.4 Thermal Fusion.5. Significance and Use5.1 Significance the increased use of geomembranes asbarrier materials to restrict fluid migration from one location toanother in various applications, and the various types ofseaming methods used in joining geomembrane sheets, hascreated a need to standar
13、dize minimum seam strength require-ments.1This specification is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.10 on Geomem-branes.Current edition approved July 15, 2012. Published September 2012. Lastprevious edition published 2008
14、as D740808. DOI: 10.1520/D7408-12.2For 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.Copyright ASTM Internationa
15、l, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.2 UseStandard seam specification provides informationas to the status of the seam. Data obtained by this standard canbe used in CQC/CQAdocuments. This test method is useful forspecification testing and for compa
16、rative purposes but does notnecessarily measure the ultimate strength that the seam mayacquire.6. Apparatus6.1 Tensile instrumentation shall meet the requirementsoutlined in Test Method D638.6.2 Grip FacesGrip faces shall be a minimum 25 mm (1in.) wide and a minimum of 25 mm (1 in.) in length. Smoot
17、hrubber, fine serrated or coarse serrated grip faces have all beenfound to be suitable for testing geomembrane seams.7. Sample Preparation7.1 Cut a sample large enough to accommodate the removalof five (5) peel specimens and five (5) shear specimens (useFig. 1)NOTE 1Larger samples sizes may be requi
18、red on site specific orproject specific or requirements for the purpose of archiving or third partytesting.7.2 Once the sample is received at the testing facility, thesample shall be acclimated at a standard laboratoryenvironment, Humidity between 50 and 70 % and a tempera-ture of 21.6 62 C (70.6 64
19、 F) for a minimum of 40 hours forall types of seams, except thermo and dielectric type seams, forthese types of seams a minimum of 4 hours at the standardlaboratory environment is required.NOTE 2 If samples are sent to the lab and testing is preformed priorto the required lab acclimating period then
20、 this must be noted on thesample results. However the sample should be at least a minimum of 40hours from the time of fabrication and lab acclimation period should be atleast one (1) hour minimum.8. Specimen Preparation8.1 Cut five specimens in peel and five in sheer as shown inFig. 1.NOTE 3Cut out
21、the 5 peel and 5 shear specimens from the sampletypically across the seam. In some conditions with seams without a crossflap, seams may have to be partially peeled open to initiate a peel test tab.8.2 Use 25.4 mm wide (1 in.) specimens8.3 Five specimens should be tested in 90 degree peel modeand fiv
22、e in shearFIG. 1 Seam SampleD7408 1228.4 The gage length for shear strength shall be 50.8 mm +the width of the seam (2 in. + the width of the seam)8.5 For peel test, position grips 13 mm (1/2 in.) on eitherside of seam9. Procedure9.1 Test peel specimens until break and record the peakvalue for each
23、specimen and the type of break per Fig. 2 forchemical, adhesive and dielectric, Fig. 2 for all dual trackseams.NOTE 4For Dual track seams test both weld tracks for peel.9.2 Test shear specimens until break and record the peakvalue for each specimen and the type of break per Fig. 2 forchemical, adhes
24、ive and dielectric, Fig. 2for all dual track seamsat 508 mm/min (20 in./min).9.3 Test Peel and Bond Seam Strength specimens at:9.3.1 Option 1 508 mm/min (20 in./min).9.3.2 Option 2 0.8 mm/min (2 in./min).NOTE 5Peel test are typically run at 50.8 mm/min and 508 mm/min(2in. /min and 20 in./min) and sh
25、ould be reported on the report as to thespeed of the test was run. Test specimens until break and record the peakvalue for each specimen.9.4 Average the peak results of the 5 specimens to obtainthe recordable result of the sample.9.5 Record one test result for the peel sample and one forthe shear sa
26、mple.9.6 All results should be rounded off to two decimals10. Mechanical Properties Minimum Properties10.1 See Table 1.NOTE 6See Specification D7176 for thickness reference of PVC10,PVC20, etc.11. Results11.1 The average of the five specimens shall meet or exceedthe minimum requirements for peel and
27、 shear.11.2 Four of the five specimens from each sample shall meetor exceed for the peel test Shear test.12. Report12.1 The report for each sample shall contain but not limitedto;12.2 All individual data to be consistent with 11.212.2.1 The Identification of the panel.12.2.2 The location of the samp
28、le.12.2.3 The reportable result of the peel test.12.2.4 Report the break type for the peel (Fig. 2).12.2.5 The reportable result of the shear test.12.2.6 Report the break type for the Bond Seam test (Fig. 2).12.2.7 Job Name.12.2.8 Sample ID or Number.12.2.9 Lot Number and/or Roll Numbers.12.2.10 Mac
29、hine and/or Operators Number.12.2.11 Other items on the test report may contain; Tem-peratures ambient and sheet, weather conditions for fieldapplications.13. Precision and Bias13.1 No statement is made as to the precision or bias at thetime of publishing14. Keywords14.1 flexible sheeting ; ; geomem
30、brane; geosynthetic; land-fill; pond liner; poly(vinyl chloride); polyvinyl chloride resin;PVC; reservoir; seams; water containment membrane; waterleakage resistanceTABLE 1 Mechanical Properties Minimum PropertiesSeam Strengths ASTM PVC 10 PVC 20 PVC 30 PVC 40 PVC 50 PVC 60Section 1 Bond SeamStrengt
31、h20 in./minTest Method D882Min20 lbs/in3.47 kN/m38.4 lbs/in.6.7 kN/m58.4 lbs/in.10 kN/m77.6 lbs/in.14 kN/m92.8 lbs/in.16 kN/m109.6 lbs/in.20 kN/mSection 2 Peel Strength2 in./minTest Method D882Min10 lbs/in1.8 kN/m12.5 lbs/in2.2 kN/m15 lbs/in2.6 kN/m15 lbs/in2.6 kN/m15 lbs/in2.6 kN/m15 lbs/in2.6 kN/m
32、Section 3 Peel Strength20 in./minTest Method D882Min10 lbs/in1.8 kN/m15 lbs/in2.2 kN/m18 lbs/in2.6 kN/m18 lbs/in3.1 kN/m18 lbs/in3.1 kN/m18 lbs/in3.1 kN/mD7408 123FIG. 2 Break Type DiagramD7408124ASTM International takes no position respecting the validity of any patent rights asserted in connection
33、 with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible t
34、echnical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful conside
35、ration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr
36、 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D7408 125
