ASTM_D_6575_-_D_6575M_-_16.pdf

Designation:D6575/D6575M16Standard Test Method forDetermining Stiffness of Geosynthetics Used as TurfReinforcement Mats(TRMs)1This standard is issued under the fixed designation D6575/D6575M;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.1.Scope1.1 This test method covers the determination of the stiff-ness of geosynthetics used as Turf Reinforcement Mats(TRM).1.2 The method is applicable to TRMs of any fiber contentand any number of components.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:2D123 Terminology Relating to TextilesD1388 Test Method for Stiffness of FabricsD1776/D1776M Practice for Conditioning and Testing Tex-tilesD4354 Practice for Sampling of Geosynthetics and RolledErosion Control Products(RECPs)for TestingD4439 Terminology for GeosyntheticsD6566 Test Method for Measuring Mass per Unit Area ofTurf Reinforcement MatsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 Federal Standards:3CCC-T-191b Textile Test Methods No.5206.23.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 bending length,n:3.1.1.1 general,adja measure of the interaction betweengeosynthetic weight and geosynthetic stiffness as shown by theway in which a geosynthetic bends under its own weight.Itreflects the stiffness of a geosynthetic when bent in one planeunder the force of gravity,and is one component of drape.3.1.1.2 DiscussionBending length is called drape stiffnessin Federal Specification CCC-T-191b.3.1.1.3 specific,adjthe cube root of the ratio of theflexural rigidity to the mass per unit area.3.1.2 flexural rigidity,n:3.1.2.1 general,adjresistance to bending.3.1.2.2 DiscussionResistance to bending or“flexural ri-gidity”is called flex stiffness in Federal Specification CCC-T-191b.3.1.2.3 specific,adjthe couple on either end of a sample ofunit width bent into unit curvature in the absence of anytension.3.1.2.4 DiscussionThe methods measure the bendinglength.Flexural rigidity is calculated directly by multiplyingthe cube of the bending length by the weight per unit area(see3.1.1.3).3.1.3 stiffness,nresistance to bending.3.2 DefinitionsFor definitions of other textile or geosyn-thetic terms used in this test method,refer to TerminologiesD123 and D4439.4.Significance and Use4.1 In general this test method is adapted from tests devel-oped for woven fabrics(previously designated as Test MethodD1388).4.2 The cantilever test method may not be suitable fortesting products that are very limp or have a marked tendencyto curl or twist at a cut edge.1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.05 on Geosyn-thetic Erosion Control.Current edition approved July 1,2016.Published July 2016.Originally approvedin 2000.Last previous edition approved in 2014 as D6575 14a.DOI:10.1520/D6575_D6575M-16.2For 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.3Available from U.S.Government Publishing Office,732 N.Capitol St.,NW,Washington,DC 20401-0001,http:/www.gpo.gov.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 Cantilever Method5.Summary of Method5.1 A specimen of the TRM is slid in a direction parallel toits long dimension,so that its end projects from the edge of ahorizontal surface.The length of overhang is measured whenthe tip of the test specimen is depressed under its own weightto the point where the line joining the tip to the edge of theplatform makes an angle of 41.5 with the horizontal.One halfof this length is the bending length of the specimen.The cubeof this quantity multiplied by the weight per unit area of thegeosynthetic is the flexural rigidity.5.2 This test method is known also as the Single CantileverTest.6.Apparatus6.1 Stiffness Tester,having the following parts:6.1.1 Horizontal Platform,with a minimum area of 18 by12 in.457.2 by 304.8 mm and