ASTM_D_8237_-_21.pdf

Designation:D823721Standard Test Method forDetermining Fatigue Failure of Asphalt-Aggregate Mixtureswith the Four-Point Beam Fatigue Device1This standard is issued under the fixed designation D8237;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 provides a procedure for determining afatigue curve that is developed using three or more strainlevels.The resulting data can be used in the fatigue models formechanistic-empirical pavement design(that is,PavementME).Failure points are determined for estimating the fatiguelife of 380 mm long by 50 mm thick by 63 mm in breadth(width)asphalt mixture beam(rectangular prism)specimenssawed from laboratory or field-compacted asphalt mixture,which are subjected to repeated flexural bending.1.2 The largest nominal maximum aggregate size(NMAS)recommended for beams 50 mm thick is 19 mm.Beams madewith an NMAS greater than 19 mm might significantly inter-fere with the material response,thereby affecting the repeat-ability of the test.1.3 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.1.4 UnitsThe values stated in SI units are to be regardedas standard.No other units of measurement are included in thisstandard,with the exception of degrees()where angle isspecified in accordance with IEEE/ASTM SI 10.1.5 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D8 Terminology Relating to Materials for Roads and Pave-mentsD75/D75M Practice for Sampling AggregatesD140/D140M Practice for Sampling Asphalt MaterialsD979/D979M Practice for Sampling Bituminous PavingMixturesD2041/D2041M Test Method for Theoretical MaximumSpecific Gravity and Density of Asphalt MixturesD2726/D2726M Test Method for Bulk Specific Gravity andDensity of Non-Absorptive Compacted Asphalt MixturesD3203/D3203M Test Method for Percent Air Voids in Com-pacted Asphalt MixturesD3549/D3549M Test Method for Thickness or Height ofCompacted Asphalt Mixture SpecimensD3666 Specification for Minimum Requirements for Agen-cies Testing and Inspecting Road and Paving MaterialsD5361/D5361M Practice for Sampling Compacted AsphaltMixtures for Laboratory TestingD7981 Practice for Compaction of Prismatic Asphalt Speci-mens by Means of the Shear Box CompactorD8079 Practice for Preparation of Compacted Slab AsphaltMix Samples Using a Segmented Rolling CompactorE4 Practices for Force Verification of Testing MachinesE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE2309/E2309M Practices for Verification of DisplacementMeasuring Systems and Devices Used in Material TestingMachinesIEEE/ASTM SI 10 American National Standard for MetricPractice2.2 AASHTO Standard:3R 30 Standard Practice for Mixture Conditioning of Hot-MixAsphalt(HMA)1This test method is under the jurisdiction of ASTM Committee D04 on Roadand Paving Materials and is the direct responsibility of Subcommittee D04.26 onFundamental/Mechanistic Tests.Current edition approved July 1,2021.Published July 2021.Originally approvedin 2018.Last previous edition approved in 2018 as D8237 18.DOI:10.1520/D8237-21.2For 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 StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.13.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 p-p,npeak-to-peak stress amplitude at