1、Designation:D519912Standard Test Method forMeasuring the Nominal Thickness of Geosynthetics1This standard is issued under the fixed designation D5199;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number
2、in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the measurement of the nominalthickness of geosynthetics,except textured and some struc-tured geomembranes where the entir
3、e surface of the presserfoot cannot come into complete contact with the geosyntheticsurface.1.2 This test method does not provide thickness values forgeosynthetics under variable normal compressive stresses.Thistest method determines nominal thickness,not necessarilyminimum thickness.1.3 The values
4、stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.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 he
5、alth practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD2905 Practice for Statements on Number of Specimens forTextiles(Withdrawn 2008)3D
6、4354 Practice for Sampling of Geosynthetics and RolledErosion Control Products(RECPs)for TestingD4439 Terminology for GeosyntheticsD5199 Test Method for Measuring the Nominal Thicknessof GeosyntheticsD5994 Test Method for Measuring Core Thickness of Tex-tured GeomembranesE691 Practice for Conducting
7、 an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 For definitions of other terms relating to geotextiles andgeomembranes used in this standard,refer to TerminologyD4439.For definition of other textile terms used in thisstandard,refer to Terminology D123.3.2 Definit
8、ions:3.2.1 pressure,nthe force or load per unit area.3.2.2 thickness(1)the distance between one planar surfaceand its opposite parallel and planar surface;(2)in the textilesthe distance between the upper and lower surfaces of thematerial,measured under a specified pressure and time.3.2.3 structured
9、geomembrane,ngeomembrane consist-ing of a flat core and protrusions on one or both sides 3.1.3 Fordefinitions of other terms relating to geotextiles and geomem-branes used in this standard,refer to Terminology D4439.4.Summary of Test Method4.1 The nominal thickness of geosynthetics is determinedby o
10、bserving the distance between two parallel surfacesconfining the tested material while under a specified pressure,after 5 seconds.5.Significance and Use5.1 Thickness is one of the basic physical properties used tocontrol the quality of many geosynthetics.Thickness valuescan be required for calculati
11、on of some geosynthetics proper-ties such as permeability and tensile stress,among others.5.2 The thickness of some geosynthetics may vary consid-erably with the applied normal load.Specific pressures andsurfaces on which they are applied are indicated in this methodto ensure all results are compara
12、ble.5.3 This test method may be used for acceptance testing ofcommercial shipments of geosynthetics for which this methodis applicable(see 1.1).NOTE1The user should be aware that the compressibility of somematerials,their rebound characteristics,and other phenomenon will affectthe thickness of some
13、geosynthetics,following the time when they arerolled up,shipped and stored.1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.03 on Perme-ability and Filtration.Current edition approved Feb.1,2012.Published February
14、2012.Originallyapproved in 1991.Last previous edition approved in 2011 as D5199 11.DOI:10.1520/D5199-12.2For 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 Doc
15、ument 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 6.Apparatus6.1 Thickness Testing Instrument The thickness gaugeshall
16、 have a base(or anvil)and a free moving presser foot platewhose planar faces are parallel to each other to 0.01 mm.Agauge with a 56.4 mm(2.22 in.)diameter presser foot,the baseshall extend at least 10 mm(3/8 in)in all directions further thanthe edge of the 2500 mm2(3.88 in2)circular presser foot,shallbe used for measurements of geotextiles,geocomposite drain-age materials,and geonets.Agauge with a 6.35 mm(0.250 in.)diameter presser foot and a base at least 6.35 mm(0.250 in)diameter shall be used