ASTM_D_6723_-_12.pdf

Designation:D672312Standard Test Method forDetermining the Fracture Properties of Asphalt Binder inDirect Tension(DT)1This standard is issued under the fixed designation D6723;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 This test method covers the determination of the failurestrain and failure stress of asphalt binders by means of a directtension test.It can be used with unaged material or withmaterial aged using Test Method D2872(RTFOT),PracticeD6521(PAV),or AASHTO T240(RTFOT)and AASHTO PP1(PAV).The test apparatus is designed for testing within thetemperature range from+6 to-36C.1.2 This test method is limited to asphalt binders containingparticulate material having dimensions less than 250 m.1.3 The values stated in SI units are to be regarded as thestandard.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:2C670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsD8 Terminology Relating to Materials for Roads and Pave-mentsD140 Practice for Sampling Bituminous MaterialsD2872 Test Method for Effect of Heat and Air on a MovingFilm of Asphalt(Rolling Thin-Film Oven Test)D6373 Specification for Performance Graded AsphaltBinderD6521 Practice for Accelerated Aging of Asphalt BinderUsing a Pressurized Aging Vessel(PAV)E1 Specification for ASTM Liquid-in-Glass ThermometersE4 Practices for Force Verification of Testing MachinesE77 Test Method for Inspection and Verification of Ther-mometersE83 Practice for Verification and Classification of Exten-someter SystemsE220 Test Method for Calibration of Thermocouples ByComparison TechniquesE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 Deutche Industrie Norm(DIN)Standard:43760 Standard for Calibrating Thermocouples32.3 AASHTO Standards:T 2404PPI(PAV)43.Terminology3.1 DefinitionsFor definitions of general terms used in thisstandard,refer to Terminology D8.3.2 Definitions of Terms Specific to This Standard:3.2.1 brittle,adjtype of failure in a direct tension testwhere the stress-strain curve is essentially linear up to the pointof failure and the failure is by sudden rupture of the testspecimen without appreciable reduction in cross-section of thespecimen.3.2.2 brittle-ductile,adjtype of failure in a direct tensiontest where the stress-strain curve is curvilinear and the failureis by sudden rupture of the test specimen.Limited reduction incross-section of the specimen occurs before rupture.3.2.3 ductile,adjtype of failure in a direct tension testwhere the specimen does not rupture but fails by flow at largestrains.3.2.4 effective gage length,nfor specimens used in thistest,the effective gauge length,Le,has been determined to be33.8 mm.This is an effective gauge length that represents theportion of the specimen that contributes to the majority of thestrain.1This test method is under the jurisdiction of ASTM Committee D04 on Roadand Paving Materials and is the direct responsibility of Subcommittee D04.44 onRheological Tests.Current edition approved Feb.1,2012.Published April 2012.Originallyapproved in 2001.Last previous edition approved in 2002 as D6723 02 which waswithdrawn January 2011 and reinstated in February 2012.DOI:10.1520/D6723-12.2For 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 Document Summary page onthe ASTM website.3Deutsches Institut fur Normung e.V.(German Standards Institute),BeuthVerlag GmbH,Burggrafenstrasse 6,10787,Berlin Germany.4Available from American Association of State Highway and TransportationOfficials(AASHTO),444 N.Capitol St.,NW,Suite 249,Washington,DC 20001,http:/www.transportation.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.5 failure,npoint at which the tensile load reaches amaximum value as the test specimen is pulled at a constant rateof elongation.3.2.6 failure strain,nthe tensile strain corresponding tothe failure stress.3.2.7 failure stress,nthe tensile stress on the test specimenwhen the load reaches a maximum value during the test methodspecified in this standard.3.2.8 gage section,nthe central portion of the specimenwhere the cross-section does not change with length.For thegeometry used in this test method,the gage section is 18 mmin length(see Fig.1).3.2.9 tensile strain,naxial strain resulting from the