ASTM_D_7369_-_20.pdf

Designation:D736920Standard Test Method forDetermining the Resilient Modulus of Asphalt Mixtures byIndirect Tension Test1This standard is issued under the fixed designation D7369;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 procedures for preparing andtesting laboratory-fabricated or field-recovered cores of asphaltmixtures to determine resilient modulus values using arepeated-load indirect tension test.1.2 The values stated in SI units are regarded as thestandard.Values in parentheses are for informational use.1.3 A precision and bias statement for this standard has notbeen developed at this time.Therefore,this standard should notbe used for acceptance or rejection of a material for purchasingpurposes.1.4 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.1.5 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-mentsD3666 Specification for Minimum Requirements for Agen-cies Testing and Inspecting Road and Paving MaterialsD6925 Test Method for Preparation and Determination ofthe Relative Density of Asphalt Mix Specimens by Meansof the Superpave Gyratory CompactorD6926 Practice for Preparation of Asphalt Mixture Speci-mens Using Marshall ApparatusD6931 Test Method for Indirect Tensile(IDT)Strength ofAsphalt Mixtures2.2 Other Document:NCHRP Project 1-28A Research Results Digest Number285Laboratory Determination of Resilient Modulus forFlexible Pavement Design,January 20043.Terminology3.1 DefinitionsDefinitions are in accordance with Termi-nology D8.3.2 Definitions of Terms Specific to This Standard:3.2.1 contact load(Pcontact),nthe vertical load placed onthe specimen to maintain a positive contact between theloading strip and the specimen.The suggested contact load is8%of the maximum load(0.08 Pmax).The contact load shouldbe not less than 22.2 N(5 lb)and no more than 89.0 N(20 lb).3.2.2 core,nan intact cylindrical specimen of pavementmaterial,which is removed from the pavement by drilling andsampling at the designated location.A core may consist of orinclude one,two,or more than two different layers.3.2.3 cyclic load(resilient vertical load,Pcyclic),nloadapplied to a specimen,which is directly used to calculateresilient modulus.Pcyclic5 Pmax2 Pcontact(1)3.2.4 haversine-shaped load form,nthe required loadpulse for the resilient modulus test.The load pulse is in theform(1-cos)/2 with the cyclic load varying from the contactload(Pcontact)to the maximum load(Pmax).3.2.5 instantaneous resilient modulus,ndetermined fromthe deformation-time plots(both horizontal and vertical)asdescribed in Section 10.3.2.6 lift,nthat part of the pavement produced withsimilar material and placed with similar equipment and tech-niques.The lift thickness is the thickness of the compacted1This 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 Nov.1,2020.Published December 2020.Originallyapproved in 2009.Last previous edition approved in 2011 as D7369 11,which waswithdrawn January 2020 and reinstated in November 2020.DOI:10.1520/D7369-20.2For 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.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.1asphalt mixture that is achieved with one pass of the laydownmachine and the subsequent compaction process and can beequal to or les