1、Designation:D4533/D4533M15Standard Test Method forTrapezoid Tearing Strength of Geotextiles1This standard is issued under the fixed designation D4533/D4533M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A
2、number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method is an index test used to measure thef
3、orce required to continue or propagate a tear in woven ornon-woven geotextiles by the trapezoid method.While usefulfor quality control and acceptance testing,the trapezoid teartest does not provide all the information needed for all designapplications and other test methods should be used.1.2 This t
4、est method is applicable to most geotextiles thatinclude woven fabrics,nonwoven fabrics,layered fabrics,knitfabrics,and felts that are used for geotextile applications.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach syste
5、m 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 theresponsibil
6、ity 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/D76M Specification for Tensile Testing Machines forTextilesD123 Terminology Relating to Textile
7、sD1776 Practice for Conditioning and Testing TextilesD2905 Practice for Statements on Number of Specimens forTextiles(Withdrawn 2008)3D4354 Practice for Sampling of Geosynthetics and RolledErosion Control Products(RECPs)for TestingD4439 Terminology for GeosyntheticsE177 Practice for Use of the Terms
8、 Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions:3.1.1 atmosphere for testing geotextiles,nair maintainedat a relative humidity of 65 6 5%and a temperature of21 6 2C 70 6 4F.3.1.2 geote
9、xtile,nany permeable textile material usedwith foundation,soil,rock,earth,or any other geotechnicalengineering related material as an integral part of a man-madeproduct,structure,or system.3.1.3 tearing strength,nthe force required to either(1)start,or(2)continue or propagate a tear in a fabric unde
10、rspecified conditions.3.1.3.1 DiscussionThis test method uses the maximumvalue of the tearing force as the tearing strength.3.1.4 For definitions of other terms used in this test method,refer to Terminology D123 or Terminology D4439.4.Summary of Test Method4.1 An outline of an isosceles trapezoid is
11、 marked on arectangular specimen cut for the determination of tearingstrength(see Fig.1),and the nonparallel sides of the trapezoidmarked on the specimen are clamped in parallel jaws of atensile testing machine.The separation of the jaws is continu-ously increased so the tear propagates across the s
12、pecimen.Atthe same time,the force developed is recorded.The tearingstrength,which is the maximum value of the tearing force,isobtained from the autographic force extension curve(see Fig.2).5.Significance and Use5.1 The trapezoid tear method is a test that produces tensionalong a reasonably defined c
13、ourse such that the tear propagatesacross the width of the specimen.The trapezoid tearingstrength for woven fabrics is determined primarily by the1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.01 on Mechani-cal P
14、roperties.Current edition approved Jan.1,2015.Published February 2015.Originallyapproved in 1991.Last previous edition approved in 2011 as D4533 11.DOI:10.1520/D4533_D4533M-15.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For An
15、nual Book of ASTMStandards volume information,refer to the standards Document 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 Stat
16、es1 properties of the yarns that are gripped in the clamps.Innonwoven fabrics,because the individual fibers are more orless randomly oriented and capable of some reorientation in thedirection of the applied load,the maximum trapezoid tearingstrength is reached when the resistance to further reorientationis greater than the force required to rupture one or more fiberssimultaneously.5.2 The trapezoid tearing strength method is useful forestimating the relative tear resistance of different fabrics
