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【英文标准名称】:StandardPracticeforUltrasonicTestingofGeomembranes
【原文标准名称】:土工薄膜超声检验的标准实施规程
【标准号】:ASTMD7006-2003
【标准状态】:现行
【国别】:
【发布日期】:2003
【实施或试行日期】:
【发布单位】:美国材料与试验协会(ASTM)
【起草单位】:D35.10
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:attenuation;geomembrane;mechanicalwaves;nondestructive;ultrasonic;wavevelocity;
【摘要】:Thispracticecoverstestarrangements,measurementtechniques,samplingmethods,andcalculationstobeusedfornondestructiveevaluationofgeomembranesusingultrasonictesting.Wavevelocitymaybeestablishedforparticulargeomembranes(forspecificpolymertype,specificformulation,specificdensity).Relationshipsmaybeestablishedbetweenvelocityandbothdensityandtensilepropertiesofgeomembranes.AnexampleoftheuseofultrasoundfordeterminingdensityofpolyethyleneispresentedinTestMethodD4883.Velocitymeasurementsmaybeusedtodeterminethicknessofgeomembranes(1,2).2Traveltimeandamplitudeoftransmittedwavesmaybeusedtoassesstheconditionofgeomembranesandtoidentifydefectsingeomembranesincludingsurfacedefects(forexample,scratches,cuts),innerdefects(forexample,discontinuitieswithingeomembranes),anddefectsthatpenetratetheentirethicknessofgeomembranes(forexample,pinholes)(3,4).Bondingbetweengeomembranesheetscanbeevaluatedusingtraveltime,velocity,orimpedancemeasurementsforseamassessment(5-10).Examplesoftheuseofultrasonictestingfordeterminingtheintegrityoffieldandfactoryseamsthroughtraveltimeandvelocitymeasurements(resultinginthicknessmeasurements)arepresentedinPracticesD4437andD4545,respectively.Anultrasonictestingdeviceisroutinelyusedforevaluatingseamsinprefabricatedbituminousgeomembranesinthefield(11).Integrityofgeomembranesmaybemonitoredintimeusingultrasonicmeasurements.Note18212;Differencesmayexistbetweenultrasonicmeasurementsandmeasurementsmadeusingothermethodsduetodifferencesintestconditionssuchaspressureappliedandprobedimensions.Anexampleisultrasonicandmechanicalthicknessmeasurements.Themethodisapplicabletotestingbothinthelaboratoryandinthefieldforparentmaterialandseams.Thetestdurationsareveryshortaswavetransmissionthroughgeomembranesoccurswithinmicroseconds.1.1Thispracticeprovidesasummaryofequipmentandproceduresforultrasonictestingofgeomembranesusingthepulseechomethod.1.2Ultrasonicwavepropagationinsolidmaterialsiscorrelatedtophysicalandmechanicalpropertiesandconditionofthematerials.Inultrasonictesting,twowavepropagationcharacteristicsarecommonlydetermined:velocity(basedonwavetraveltimemeasurements)andattenuation(basedonwaveamplitudemeasurements).Velocityofwavepropagationisusedtodeterminethickness,density,andelasticpropertiesofmaterials.Attenuationofwavesinsolidmaterialsisusedtodeterminemicrostructuralpropertiesofthematerials.Inaddition,frequencycharacteristicsofwavesareanalyzedtoinvestigatethepropertiesofatestmaterial.Traveltime,amplitude,andfrequencydistributionmeasurementsareusedtoassesstheconditionofmaterialstoidentifydamageanddefectsinsolidmaterials.Ultrasonicmeasurementsareusedtodeterminethenatureofmaterials/mediaincontactwithatestspecimenaswell.Measurementsareconductedinthetime-domain(timeversusamplitude)orfrequency-domain(frequencyversusamplitude).1.3Measurementsofoneormoreultrasonicwavetransmissioncharacteristicsaremadebasedontherequirementsofthespecifictestingprogram.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitat......
【中国标准分类号】:W59
【国际标准分类号】:59_080_70
【页数】:10P.;A4
【正文语种】: