ASTM_D_7466_-_D_7466M_-_10_2015e1.pdf

Designation:D7466/D7466M10(Reapproved 2015)1Standard Test Method forMeasuring Asperity Height of Textured Geomembranes1This standard is issued under the fixed designation D7466/D7466M;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.1NOTEDesignation was changed to dual and units information was corrected editorially in June 2015.1.Scope1.1 This test method covers a procedure to measure theasperity height of textured geomembranes.1.2 This test method does not provide for measurement ofthe spacing between the asperities nor of the complete profileof the textured surface.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D4439 Terminology for GeosyntheticsD5994/D5994M Test Method for Measuring Core Thicknessof Textured GeomembranesE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE2554 Practice for Estimating and Monitoring the Uncer-tainty of Test Results of a Test Method Using ControlChart Techniques3.Terminology3.1 For definitions of other terms used in this test method,refer to Terminology D4439.3.2 Definitions:3.2.1 asperity,nthe individual projections of polyethylenethat extend above the core surface of a textured geomembraneresulting in the textured surface profile.3.2.2 core thickness,nthe average thickness of a texturedgeomembrane as measured using Test Method D5994/D5994M.3.2.3 geomembrane,nan essentially impermeable geosyn-thetic composed of one or more synthetic sheets.D44393.2.4 setting block,nthe component part of a depth gaugethat rests on top of the asperities.3.2.5 thickness,n the perpendicular distance between onesurface and its opposite.3.2.6 thickness gauge contact point,nthe tip of a thick-ness gauge which contacts the base sheet of the geomembranesurface.4.Summary of Test Method4.1 The asperity height of a textured geomembrane ismeasured with a depth gauge,the setting block of which restson the top of the asperities while the contact point extends tothe sheets core surface.4.2 The asperity height of a textured geomembrane iscalculated as the average value of ten(10)individual measure-ments taken across the roll width of the sample under investi-gation.5.Significance and Use5.1 The asperity height is an index property used to quantifyone of the physical attributes related to the surface roughnessof textured geomembranes.5.2 This test method is applicable to all currently availabletextured geomembranes that are deployed as manufacturedgeomembrane sheets.1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.10 on Geomem-branes.Current edition approved May 1,2015.Published June 2015.Originallyapproved in 2008.Last previous edition approved in 2010 as D7466-10.DOI:10.1520/D7466_D7466M-10R15E01.2For 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 States1 6.Apparatus6.1 Depth GaugeThe depth gauge shall consist of threecomponents that conform the requirements of this section;adial indicator,a setting block and a contact point with exten-sion.6.1.1 Dial Indicatorcapable of measuring to depth of atleast 2.5 mm 0.10 in.with an accuracy of 60.025 mm0.001 in.6.1.2 Setting Blockthe setting block shall have a basedimension of 50 mm to 63.5 mm long by 20 mm to 12.7 mmwide 2.0 in.to 2.5 in.long by 0.75 in.to 0.50 in.wide and aheight of 15 mm 0.60 in.6.1.3 Contact Point with ExtensionThe contact point is1.3 mm 0.051 in.in diameter with the tip tapered to a point.An extension of approximately 17 mm 0.66 in.is required toachieve the necessary travel beyond the base surface of thesetting block.The contact point should protrude at least 10 mmbelow the setting block when not in use in order to ensure thata competent“zero”setting is achieved.See Figs.1-3.6.1.4 The mass of the depth gauge fully assembled with thedial indicator,se