ASTM_D_8044_-_16.pdf

Designation:D804416Standard Test Method forEvaluation of Asphalt Mixture Cracking Resistance usingthe Semi-Circular Bend Test(SCB)at IntermediateTemperatures1This standard is issued under the fixed designation D8044;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 procedures for preparation,testing,and measurement of asphalt mixture cracking resis-tance at Long Term Pavement Performance(LTPP)databaseintermediate temperatures using semi-circular bend(SCB)geometry laboratory prepared or pavement core asphalt mixsamples tested monotonically.The SCB sample is a half-diskwith a notch cut parallel to the loading and vertical axis.Thetest method describes the determination of the critical strainenergy release rate,Jc,and other parameters determined fromthe load-displacement curve.These parameters can be used torank the resistance of asphalt mixtures to cracking.1.2 The text of this standard references notes and footnoteswhich provide explanatory material.These notes and footnotes(excluding those in tables and figures)shall not be consideredas requirements of the standard.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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:2D979/D979M Practice for Sampling Bituminous PavingMixturesD2041/D2041M Test Method for Theoretical MaximumSpecific Gravity and Density of Bituminous Paving Mix-turesD2726/D2726M Test Method for Bulk Specific Gravity andDensity of Non-Absorptive Compacted Bituminous Mix-turesD3203/D3203M Test Method for Percent Air Voids in Com-pacted Dense and Open Bituminous Paving MixturesD3666 Specification for Minimum Requirements for Agen-cies Testing and Inspecting Road and Paving MaterialsD5361/D5361M Practice for Sampling Compacted AsphaltMixtures for Laboratory TestingD6373 Specification for Performance Graded AsphaltBinderD6857/D6857M Test Method for Maximum Specific Grav-ity and Density of Bituminous Paving Mixtures UsingAutomatic Vacuum Sealing MethodD6925 Test Method for Preparation and Determination ofthe Relative Density of Asphalt Mix Specimens by Meansof the Superpave Gyratory CompactorE4 Practices for Force Verification of Testing MachinesE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE178 Practice for Dealing With Outlying ObservationsE399 Test Method for Linear-Elastic Plane-Strain FractureToughness KIcof Metallic MaterialsE2309/E2309M Practices for Verification of DisplacementMeasuring Systems and Devices Used in Material TestingMachinesE3029 Practice for Determining Relative Spectral Correc-tion Factors for Emission Signal of Fluorescence Spec-trometers2.2 AASHTO Standards:3R30 Practice for Mixture Conditioning of Hot Mix Asphalt(HMA)M320 Standard Specification for Performance-Graded As-phalt BinderM332 Standard Specification for Performance-Graded UsingMultiple Stress Creep Recovery(MSCR)Test1This test method is under the jurisdiction of ASTM Committee D04 on Roadand Paving Materials and is the direct responsibility of Subcommittee D04.20 onMechanical Tests of Asphalt Mixtures.Current edition approved July 1,2016.Published August 2016.DOI:10.1520/D8044-16.2For 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 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.Terminology3.1 Definitions:3.1.1 Jccritical strain energy release rate(kJ/m2),valueused to evaluate mixture resistance to cracking.3.1.2 Ustrain energy to failure(kJ)is the area under theloading portion of the load versus deflection curves,up to themaximum load measured for each notch depth.4.Summary of Test Method4.1 A semi-circular specimen is loaded monotonically untilfracture failure occurs under a constant rate of deformation ina three-point bending load configuration.The load and defor-mation are continuously recorded and are used to compute thestrain energy for a given notch depth.The test is repeated atmultiple notch depths to compute the critical strain energyrelease rate,Jc.High Jcvalues are desirable for fra