ASTM_D_5820_-_95_2018.pdf

Designation:D582095(Reapproved 2018)Standard Practice forPressurized Air Channel Evaluation of Dual-SeamedGeomembranes1This standard is issued under the fixed designation D5820;the number immediately following the designation indicates the year oforiginal adoption 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 practice covers a nondestructive evaluation of thecontinuity of parallel geomembrane seams separated by anunwelded air channel.The unwelded air channel between thetwo distinct seamed regions is sealed and inflated with air to apredetermined pressure.Long lengths of seam can be evaluatedby this practice more quickly than by other common nonde-structive tests.1.2 This practice should not be used as a substitute fordestructive testing.Used in conjunction with destructivetesting,this method can provide additional information regard-ing the seams undergoing testing.1.3 This practice supercedes Practice D4437/D4437M forgeomembrane seams that include an air channel.PracticeD4437/D4437M may continue to be used for other types ofseams.The user is referred to the referenced standards,or toEPA/530/SW-91/051 for additional information regardinggeomembrane seaming techniques and construction qualityassurance.1.4 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.1.5 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:2D4437/D4437M Practice for Nondestructive Testing(NDT)for Determining the Integrity of Seams Used in JoiningFlexible Polymeric Sheet GeomembranesD4439 Terminology for GeosyntheticsD4491/D4491M Test Methods for Water Permeability ofGeotextiles by Permittivity2.2 EPA Standard:3EPA/530/SW-91/051 Technical Guidance Document:In-spection Techniques for the Fabrication of GeomembraneField Seams3.Terminology3.1 Definitions:3.1.1 dual seam,na geomembrane seam with two parallelwelded zones separated by an unwelded air space.3.1.2 DiscussionThe dual seam itself can be made by anumber of methods,the most common being the hot wedgetechnique.Other possible methods include hot air and ultra-sonic bonding techniques.3.1.3 geomembrane,nan essentially impermeable geosyn-thetic composed of one or more synthetic sheets.3.1.4 DiscussionIn geotechnical engineering,“imperme-able”essentially means that no measurable liquid flowsthrough a geosynthetic when tested in accordance with TestMethods D4491/D4491M.3.1.5 seam,na permanent joining of two or more materi-als.3.2 For definitions of other terms,see Terminology D4439.4.Summary of Practice4.1 This practice utilizes a dual seam where an air channelexists between the two welded zones.Both ends of the air1This practice is under the jurisdiction of ASTM Committee D35 on Geosyn-thetics and is the direct responsibility of Subcommittee D35.10 on Geomembranes.Current edition approved Feb.1,2018.Published February 2018.Originallyapproved in 1995.Last previous edition approved in 2011 as D5820 95(2011).DOI:10.1520/D5820-95R18.2For 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 the Superintendent of Documents,U.S.Government PrintingOffice,Washington,DC 20402.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.1 channel are sealed and then a pressure gauge is attached to theair space.Air pressure is applied and the gauge is monitored forexcessive gauge air pressure drop.4.2 Air pressures used in this practice are related to thethickness,stiffness,and material type of the geomembrane.4.3 The minimum monitoring time is recommended to be2 min following stabilization of the pressure.4.4 Maximum allowable loss of air pressure varies depend-ing upon thickness,stiffness,and type of material of thegeomembrane.5.Significance and Use5.1 The increased use of geomembranes as barrier materialsto restrict liquid or gas movement,and the c