ASTM_D_7177_-_D_7177M_-_21.pdf

Designation:D7177/D7177M21Standard Specification forAir Channel Evaluation of Polyvinyl Chloride(PVC)DualTrack Seamed Geomembranes1This standard is issued under the fixed designation D7177/D7177M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.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 specification covers a nondestructive evaluation ofthe strength and continuity of parallel PVC geomembraneseams separated by an unwelded air channel.The unwelded airchannel between the two distinct seamed regions is sealed andinflated with air to a predetermined pressure.Long lengths ofseam can be evaluated by this specification more quickly thanby other common nondestructive tests.1.2 This specification can be used as a substitute fordestructive testing or used in conjunction with destructivetesting.1.3 This specification covers PVC sheet 0.760 mm0.030 in.and thicker.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system are not necessarily exact equivalents;therefore,toensure conformance with the standard,each system shall beused independently of the other,and values from the twosystems shall not be combined.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 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 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:2D4439 Terminology for Geosynthetics3.Terminology3.1 Definitions:3.1.1 dual seam,na geomembrane seam with two parallelwelded zones separated by an unwelded air space.3.1.1.1 DiscussionThe dual seam itself can be made by anumber of methods;hot wedge,hot air,and ultrasonic bondingare all typical techniques.3.1.2 geomembrane,nan essentially impermeable geosyn-thetic composed of one or more synthetic sheets.3.1.3 seam,na permanent joining of two or more materi-als.3.2 For definitions of other terms,see Terminology D4439.4.Summary of Specification4.1 This specification utilizes a dual seam where an airchannel exists between the two welded zones.Both ends of theair channel are sealed and then a pressure gauge is attached tothe air space.Air pressure is applied and the gauge ismonitored.4.2 Air pressures used in this specification are related to theambient temperature of the PVC geomembrane and can beused for thickness 0.760 mm 0.030 in.and thicker PVCgeomembrane.The air pressure is not dependant on thicknessof the PVC geomembrane being tested.4.3 The minimum monitoring time is recommended to be12min(30 s)following stabilization of the pressure.5.Significance and Use5.1 The increased use of geomembranes as barrier materialsto restrict liquid or gas movement,and the common use of dual1This specification is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.06 on Geosyn-thetic Specifications.Current edition approved Jan.1,2021.Published January 2021.Originallyapproved in 2005.Last previous edition approved in 2015 as D7177/D7177M 05(2015)1.DOI:10.1520/D7177_D7177M-21.2For 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 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 theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.track seams in joining these sheets,has created a need for astandard nondestructive test by which the quality of the seamscan be assessed for continuity,watertightness,and strength.The test is also intended to provide an indication of thephysical peel strength of the PVC seam.5.2 This specification recommends an air pressure testwithin the channel created between dual seamed trackswhereby the presence of un-bonded sections or channels,voids,discontinuities,foreign objects,and the like,in theseamed region can be identified.5.3 This technique is intended for use on seams of PVCgeomembrane sheets 0.760 mm 0.030 in.and thicker fo