ASTM_D_5494_-_93_2011.pdf

Designation:D549493(Reapproved 2011)Standard Test Method for theDetermination of Pyramid Puncture Resistance ofUnprotected and Protected Geomembranes1This standard is issued under the fixed designation D5494;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 The test method is to be used as an index test todetermine the pyramid puncture resistance of geomembranesand,or both,geomembranes protected by non-woven geotex-tiles and other puncture protective geosynthetics.1.2 The test method measures the increase of the pyramidpuncture resistance due to the use of protective non-wovengeotextiles with geomembranes.1.3 The values stated in SI units are to be regarded as thestandard value.The values stated in parentheses are providedfor information only.1.4 This standard does not purport to address all of thesafety problems,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:2D76 Specification for Tensile Testing Machines for TextilesD4354 Practice for Sampling of Geosynthetics and RolledErosion Control Products(RECPs)for TestingD4439 Terminology for GeosyntheticsD4491 Test Methods for Water Permeability of Geotextilesby Permittivity3.Terminology3.1 Definitions:3.1.1 atmosphere for testing geosynthetics,nair main-tained at a relative humidity between 50 to 70%and atemperature of 21 6 2C(70 6 4F).3.1.2 geomembrane,nan essentially impermeable geosyn-thetic composed of one or more synthetic sheets.3.1.2.1 DiscussionIn geotechnical engineering,essen-tially impermeable means that no measurable liquid flowsthrough a geosynthetic when tested in accordance with TestMethod D4491.3.1.3 geotextile,na permeable geosynthetic comprisedsolely of textiles.3.1.3.1 DiscussionCurrent manufacturing techniques pro-duce non-woven fabrics,knitted(non-tubular)fabrics,andwoven fabrics.3.1.4 For other terms,see Terminology D4439.4.Summary of Test Method4.1 A test specimen is clamped without tension betweencircular plates of a ring clamp attachment secured in acompression press or tensile testing machine.Aforce is exertedagainst the center of the unsupported or supported portion ofthe test specimen by a solid steel pyramid attached to a loadindicator until rupture of the specimen occurs.The maximumload and elongation recorded is the value of the punctureresistance of the specimen.5.Significance and Use5.1 The pyramid method of puncture resistance is an indextest for the determination of the puncture resistance of unpro-tected geomembranes or geomembranes protected with non-woven geotextiles and other puncture protective geosynthetics.5.1.1 The purpose of this test method is to establish an indexvalue of puncture resistance by providing standard criteria anda basis for uniform reporting.5.2 This test method may be used for acceptance testing ofcommercial shipments of geomembranes and geomembranesprotected with non-woven geotextiles;however,caution isadvised since information about between laboratory precisionis incomplete.6.Apparatus6.1 Test Set UpA compression press with a reading forceaccuracy of at least 2 N(0.5 lb)is necessary.The press mustmaintain a constant test speed and should be provided with anautomatic chart recorder for the force vs.deformation behavior.A clamping device for the test sample,a special piston and1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of D35.10 on Geomembranes.Current edition approved June 1,2011.Published July 2011.Originally approvedin 1993.Last previous edition approved in 2006 as D549493(2006).DOI:10.1520/D5494-93R11.2For 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 electrical signal equipment for determining the puncture loadare the additional pieces of test equipment needed.Also,atensile testing machine conforming to the requirements ofSpecification D76 can be utilized in a compression mode forthis test method.The equipment set up shall provide a constantrate of speed,reading accuracy of at least 2 N(0.5 lb)and beprovided with an automatic chart recorder for load vs.defor-mation.Additional equipment required by this test method isdescribed below.6.2 Clamping DeviceThe upper and lower fixing ringclamp,dimensions of which are shown on Fig.1a and 1b.Thelower fixing ring shall be provided with a circular reces