ASTM_D_7006_-_03_2013.pdf

Designation:D700603(Reapproved 2013)Standard Practice forUltrasonic Testing of Geomembranes1This standard is issued under the fixed designation D7006;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 provides a summary of equipment andprocedures for ultrasonic testing of geomembranes using thepulse echo method.1.2 Ultrasonic wave propagation in solid materials is corre-lated to physical and mechanical properties and condition ofthe materials.In ultrasonic testing,two wave propagationcharacteristics are commonly determined:velocity(based onwave travel time measurements)and attenuation(based onwave amplitude measurements).Velocity of wave propagationis used to determine thickness,density,and elastic properties ofmaterials.Attenuation of waves in solid materials is used todetermine microstructural properties of the materials.Inaddition,frequency characteristics of waves are analyzed toinvestigate the properties of a test material.Travel time,amplitude,and frequency distribution measurements are usedto assess the condition of materials to identify damage anddefects in solid materials.Ultrasonic measurements are used todetermine the nature of materials/media in contact with a testspecimen as well.Measurements are conducted in the time-domain(time versus amplitude)or frequency-domain(fre-quency versus amplitude).1.3 Measurements of one or more ultrasonic wave transmis-sion characteristics are made based on the requirements of thespecific testing program.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D4437 Practice for Non-destructive Testing(NDT)for De-termining the Integrity of Seams Used in Joining FlexiblePolymeric Sheet GeomembranesD4545 Practice for Determining the Integrity of FactorySeams Used in Joining Manufactured Flexible SheetGeomembranes(Withdrawn 2008)3D4883 Test Method for Density of Polyethylene by theUltrasound TechniqueE1316 Terminology for Nondestructive Examinations3.Terminology3.1 Definitions:3.1.1 atmosphere for testing geomembranes,nair main-tained at a relative humidity of 50 to 70%and a temperatureof 21 6 1C.3.1.2 geomembrane,nan essentially impermeable geosyn-thetic composed of one or more synthetic sheets.3.1.3 For definitions of terms related to ultrasonic testing,refer to Terminology E1316.4.Summary of Practice4.1 Mechanical waves are introduced to a geomembranefrom a surface of the material using an ultrasonic transducer.Transmission characteristics of the waves in the geomembraneare determined.The measured characteristics are used toevaluate certain properties and condition of geomembranes.5.Significance and Use5.1 This practice covers test arrangements,measurementtechniques,sampling methods,and calculations to be used fornondestructive evaluation of geomembranes using ultrasonictesting.1This 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 May 1,2013.Published May 2013.Originallyapproved in 2003.Last previous edition approved in 2008 as D700603(2008).DOI:10.1520/D7006-03R13.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.2 Wave velocity may be established for particulargeomembranes(forspecificpolymertype,specificformulation,specific density).Relationships may be estab-lished between velocity and both density and tensile propertiesof geomembranes.An example of the use of ultrasound fordetermining density of polyethylene is presented in TestMethod D4883.Velocity measurements may be used to deter-mine thickness of geomembranes(1,2).4Travel time andamplitude of transmitted waves may be used to assess thecondition of geomembranes and to identify defects in geomem-branes including surface defects(for example,scratches,cuts),innerdefects(forexample,discontinuitieswithingeomembranes),and defects that penetrate the entire thicknessof geomembranes(for example,pinholes)(3,4).Bondingbetween geomembrane sheets can be evaluated using traveltime,