ASTM_D_7405_-_15.pdf

Designation:D740515Standard Test Method forMultiple Stress Creep and Recovery(MSCR)of AsphaltBinder Using a Dynamic Shear Rheometer1,2This standard is issued under the fixed designation D7405;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 percentrecovery and non-recoverable creep compliance of asphaltbinders by means of Multiple Stress Creep and Recovery(MSCR)testing.The MSCR test is conducted using theDynamic Shear Rheometer(DSR)at a specified temperature.1.2 This standard is appropriate for unaged material,mate-rial aged in accordance with Test Method D2872(RTFO),material aged in accordance with Practice D6521(PAV),andmaterial aged in accordance with both Test Method D2872 andPractice D6521.NOTE1The majority of development work on this test method wasperformed on material aged in accordance with Test Method D2872(RTFO).1.3 The percent recovery is intended to provide a means todetermine the presence of elastic response and stress depen-dence of polymer modified and unmodified asphalt binders.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3C670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsD8 Terminology Relating to Materials for Roads and Pave-mentsD2872 Test Method for Effect of Heat and Air on a MovingFilm of Asphalt(Rolling Thin-Film Oven Test)D5801 Test Method for Toughness and Tenacity of Bitumi-nous MaterialsD6084 Test Method for Elastic Recovery of Asphalt Mate-rials by DuctilometerD6373 Specification for Performance Graded AsphaltBinderD6521 Practice for Accelerated Aging of Asphalt BinderUsing a Pressurized Aging Vessel(PAV)D7175 Test Method for Determining the Rheological Prop-erties of Asphalt Binder Using a Dynamic Shear Rheom-eter2.2 AASHTO Standards:4M 332 Specification for Performance-Graded AsphaltBinder Using Multiple Stress Creep Recovery(MSCR)TestT 350 Method of Test for Multiple Stress Creep Recovery(MSCR)Test of Asphalt Binder Using a Dynamic ShearRheometer(DSR)3.Terminology3.1 DefinitionsFor definitions of general terms used in thisstandard,refer to Terminology D8.3.1.1 creep and recovery,na standard rheological testprotocol whereby a specimen is subjected to a constant load fora fixed time period then allowed to recover at zero load for afixed time period.3.1.2 non-recoverable creep compliance(Jnr),nthe re-sidual strain in a specimen after a creep and recovery cycledivided by the stress applied in kPa.4.Summary of Test Method4.1 This test method is used to determine the presence ofelastic response in an asphalt binder under shear creep andrecovery at two stress levels at a specified temperature.For1This 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 Dec.1,2015.Published January 2016.Originallyapproved in 2008.Last previous edition approved in 2010 as D7405 10a.DOI:10.1520/D7405-15.2This test method is based on a work product of the Federal HighwayAdministration.A similar standard is published as AASHTO TP 70.3For 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.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 performance grade(PG)binders,the specified temperature willtypically be the PG high temperature without grade bumping asdetermined in Specification D6373 or AASHTO M 332.Sample preparation and apparatus are in accordance with TestMethod D7175 using the 25-mm parallel plate geometry witha 1-mm gap setting.The sample is loaded at constant stress for1 s then allowed to recover for 9 s.Twenty creep and recoverycycles are run at 0.100 kPa creep stress followed by ten creepand recovery cycles at 3.200 kPa creep stress.5.Significance and Use5.1 This test method is used to identify the presence ofelastic response in a binder and the change in elastic responseat two different stress levels.Non-recoverable cree