ASTM_D_6241-14.pdf

Designation:D6241-14INTERNATIONALStandard Test Method forStatic Puncture Strength of Geotextiles and Geotextile-Related Products Using a 50-mm Probe1This standard is issued under the fixed designation D6241;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.Scopeof other terms relating to geosynthetics used in this test1.1 This test method is an index test used to measure themethod,refer to Terminology D4439.force required to puncture a geotextile and geotextile-related3.2 Definitions of Terms Specific to This Standard:products.The relatively large size of the plunger provides a3.2.1 atmoshere for testing geotextiles,n-air maintained atmultidirectional force on the geotextile.a relative humidity of 50 to 70%and a temperature of 21 1.2 The values stated in SI units are to be regarded as the2C(704F).standard.The values given in parentheses are for information3.2.2 geotextile,n-a permeable geosynthetic composedonly.solely of textiles.1.3 This standard does not purport to address all of the3.2.3 puncture resistance,n-the inherent resisting mecha-safety concerns,if any,associated with its use.It is thenism of the test specimen to the failure by a penetrating orresponsibility of the user of this standard to establish appro-puncturing object.priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.4.Summary of Test Method2.Referenced Documents4.1 A test specimen is clamped without tension betweencircular plates and secured in a tensile or compression testing2.1 ASTM Standards:2machine,or both.A force is exerted against the center of theD76/D76M Specification for Tensile Testing Machines forunsupported portion of the test specimen by a steel plungerTextilesattached to the load indicator until rupture occurs.The maxi-D123 Terminology Relating to Textilesmum force is the value of puncture strength.D1776 Practice for Conditioning and Testing TextilesD1883 Test Method for CBR(California Bearing Ratio)of5.Significance and UseLaboratory-Compacted Soils5.1 This test method for determining the puncture strengthD4354 Practice for Sampling of Geosynthetics and Rolledof geotextiles is to be used by the industry as an index ofErosion Control Products(RECPs)for TestingD4439 Terminology for Geosyntheticspuncture strength.The use of this test method is to establish anindex value by providing standard criteria and a basis forE691 Practice for Conducting an Interlaboratory Study touniform reporting.Determine the Precision of a Test Method5.2 This test method is considered satisfactory for accep-NoTE 1-Test Method D1883 describes a mold(CBR mold)that can beused for this test method.tance testing of commercial shipments of geotextiles.5.3 In case of a dispute arising from differences in reported3.Terminologytest results when using this test method for acceptance testing3.1 Definitions-For definitions of other textile terms usedof commercial shipments,the purchaser and the supplierin this test method,refer to Terminology D123.For definitionsshould conduct comparative tests to determine if there is astatistical bias between their laboratories.Competent statisticalThis test method is under the jurisdiction of ASTM Committee D35 onassistance is recommended for the investigation of bias.As aGeosynthetics is the direct responsibility of Subcommittee D35.01 on Mechanicalminimum,the two parties should take a group of test speci-PropertiesCurrent edition approved July 1,2014.Published July 2014.Originally approvedmens that are as homogeneous as possible and that are from ain 1998.Last previous edition approved in 2009 as D6241-04(2009).DOI:lot of the type in question.The test specimens then should be10.1520/D6241-14.randomly assigned in equal numbers to each laboratory for2For referenced ASTM standards,visit the ASTM website,www.astm.org,ortesting.The average results from the two laboratories should becontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page oncompared using Students t-test for unpaired data and anthe ASTM website.acceptable probability level chosen by the two parties beforeCopyright C ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States|D6241-14the testing is begun.If a bias is found,either its cause must besecuring the ring clamp assemblage is suggested to be 11 mmfound and corrected,or the purchaser and the supplier must(7/16 in.)and equally spaced at a diameter of 220 mm(8.7 in.).agree to interpret future test results in the light of the knownThe surfaces of these plates can consist of grooves with rubberbias.O-rings or coarse sandpaper bonded onto opposing surfaces.It5.4 This test method is not applicable to materials that areis suggested that 9.5-mm(3/8-in.)bolts be welded to themanufactured in sizes that are too small to be placed into thebottom plate so that the top plate can be placed over the boltstest apparatus in accordance with the procedures in this testand nuts easily tightened.A guide block may be used to helpmethod.Furthermore,it is not appropriate to separate plies ofseat the material being clamped.Other clamps that eliminatea geosynthetic or geocomposite for use in this test method.slippage are acceptable.See Fig.2 and Fig.3.6.Apparatus7.Sampling6.1 Testing Machine,must be constant-rate-of extension7.1 Lot Sample-In the absence of other guidelines,divide(CRE)type,with autographic recorder conforming to thethe product into lots and take lot samples as specified inrequirement of Specification D76/D76M.Practice D4354.6.2 Plunger;with a flat diameter of 50 1 mm with a radial7.2 Laboratory Sample-Consider the units in the lotedge of 2.5 0.5 mm.See Fig.1.sample as the units in the laboratory sample.For the laboratory6.3 Clamping Apparatus,consisting of concentric platessample,take a full width sample of sufficient length along thewith an internal diameter of 150 mm(5.9 in.),capable ofselvage or edge of the roll so that the requirements of 7.3clamping the test specimen without slippage(limit slippage ofthrough 7.5.2 can be met.Exclude the inner and outer wraps oftest specimen to 5 mm).The external diameter is suggested tothe roll or any material containing folds,crushed areas,or otherbe 250 mm(9.8 in.).The diameter of the holes used fordistortions not representative of the sample lot.Shaft far mountingin pressPolishedPolishedR2.505501NOTE 1-All dimensions are in millimetres.NoTE 2-This diagram is not to scale.FIG.1 Plunger2D6241-14Tensile toad cellTestPlungerspemenhoiderClampingringsPlungerCross nead,?R2Inside edges tobe turned sothey are notsharpExamole of detais of serrated surfacs50:1150=2NoTE 1-All dimensions are in millimetres.NoTE 2-This diagram is not to scale.FIG.2 Typical Arrangement for Test on Tensile Testing Machine(Method A)7.3 Remove test specimens from the laboratory sample in a7.4 Test Specimens-From each unit in the laboratoryrandomly distributed pattern across the width with no specimensample,cut the specimens so that the edge of specimen willtaken nearer the selvage of fabric edge than 1/20 of the fabricextend beyond the edge of the clamp by 10 mm(0.39 in.)in allwidth or 150 mm(6 in.),whichever is the smaller,unlessdirections.otherwise specified.3D6241-14Hload cellCross headPlungerClamping rngsTest speamenInside edges tobe turned so theyare not sharpR2501150:2NOTE 1-All dimensions are in millimetres.NoTE 2-The diagram is not to scale.FIG.3 Typical Arrangement for Test on Compression Testing Machine(Method B)7.5 Number of Specimens-Unless otherwise agreed upon,n=(/A)2(1)as when provided in an applicable material specification,takewhere:a number of test specimens per laboratory sample such that theuser may expect at the 95%probability level that the test resultn=number of test specimens(rounded upward to a wholeis not more than 5.0%of the average above or below the truenumber),average of sample.Determine the number of specimens perv=reliable estimate of the coefficient of variation forsample as follows:individual observations on similar materials in the users7.5.1 Reliable Estimate of v-When there is a reliablelaboratory under conditions of single-operationestimate of v based upon extensive past records for similarprecision,%,materials tested in the users laboratory as directed in this testt=the value of Students t one-sided limits,a 95%method,calculate the required number of specimens as fol-probability level,and the degrees of freedom,associatedwith the estimate of v,andlows:4D6241-14A=5.0%of the average,the value of the allowable9.4 If slippage greater than 5 mm is observed,the test onvariation.that specimen should be discarded and a new specimen shouldbe obtained.7.5.2 No Reliable Estimate of v-When there is no reliableestimate of v for the users laboratory,the equation given in9.5 Test at a machine speed of 50 mm/min(approximately 27.5.1 should not be used directly.Instead,specify the fixedin./min)until the puncture rod completely ruptures the testnumber(10)of specimens.The number of specimens isspecimen.Read the puncture strength and displacement fromcalculated using v=9.5%of the average.These values for vthe greatest force registered on the recording instrument duringare somewhat larger than usually found in practice.When athe test.For the testing of composite geotextiles,there may bereliable estimate of v for the users laboratory becomesa double peak.If so,the initial value should be reported evenavailable,the equation given in 7.5.1 usually will require fewerif the second peak is higher than the first one.than the fixed number of specimens.10.CalculationNorE 2-If the material to be tested is known to have different10.1 Calculate the average of the puncture strength for allcharacteristics on the two sides,for example,physical characteristics of astest results as read directly from the recording instrument.a consequence of the manufacturing process,then the complete test shallbe carried out separately on each face.11.Report11.1 State that the material was tested in accordance with8.ConditioningTest Method D6241.State the manner in which the specimens8.1 Bring the specimens to moisture equilibrium in thewere conditioned.Describe the material or product sample andatmosphere for testing geotextiles.Equilibrium is considered tothe method of sampling used.have been reached when the increase in mass of the specimen11.2 Report the following information:in successive weightings made at intervals of not less than 2 h11.2.1 The method of holding the test specimen in thedoes not exceed 0.1%of the mass of the specimen.In generalclamping device.practice,the industry approaches equilibrium from the“as11.2.2 The average puncture strength of the specimensreceived side.tested.11.2.3 The variation of data within each group of speci-NoTE 3-It is recognized that in practice geotextiles materials fre-quently are not weighted to determine when moisture equilibrium hasmens.been reached.While such a procedure cannot be accepted in cases of11.2.4 The variation,if any,from the described test method.dispute,it may be sufficient in routine testing to expose the material to the11.3 Upon request,the graph of plunger force versus dis-standard atmosphere for testing for a reasonable period of time before thespecimens are tested.At least 24 h has been found acceptable in mostplacement.A typical graph is given in Fig.4.cases.However,certain fibers may exhibit slow moisture equalization12.Precision and Biasrates from the as received wet side.When this is known,a precondi-tioning cycle,as described in Practice D1776,may be agreed upon12.1 Precision.between contractual parties.12.1.1 Interlaboratory Testing Programs-An inter-laboratory testing program(ILS)was performed in 2003.The9.Proceduredesign of the experiment,similar to that of Practice E691.A9.1 Select the load range of the tensile testing machine such270-g/m2(8-oz/sy)needle-punched nonwoven geotextile and athat the rupture occurs between 10 and 90%of the full-scale540-g/m2(16-oz/sy)needle-punched nonwoven geotextileload.were circulated to eight laboratories.12.1.2 Test Results-The precision information is presented9.2 Center and secure the test specimen between the holdingin Table 1 for the four materials.The average values listed forplates ensuring that the test specimen extends to or beyond thethe strength test results are in units of N(Ibs).outer edges of the clamping plates.12.2 Bias-The procedure in this test method for measuring9.3 Mark the test specimen along the inside circumferencethe static puncture strength of geotextiles using a 50-mm probeof the holding container.This allows for a measurement ofhas no bias because the values of puncture strength can only bepotential slippage of the specimen.defined in terms of a test method.5