Designation:E1859/E1859M−11(Reapproved2015)StandardTestMethodforFrictionCoefficientMeasurementsBetweenTireandPavementUsingaVariableSlipTechnique1ThisstandardisissuedunderthefixeddesignationE1859/E1859M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthemeasurementofthelongi-tudinalfrictioncoefficientwithameasurementdevicethatimposesbraking-slipbetweenatireandasurfaceforthefullrangeofbraking-slipspeedvalues.1.2Thistestmethodutilizesaseriesofincrementalsinglemeasurementsoffrictionforceonabrakedtestwheelasitispulledoverawettedorcontaminatedpavementsurface.Therotationalvelocityofthebrakedwheelisfeedbackcontrolledinordertogiveapredeterminedvariableslipratiogradientinaccordancewithsetprogramparameters.Thetestwheeliskeptunderaconstantstaticnormalloadandataconstantlongitu-dinalspeedoftravel.Itsmajorplaneisperpendiculartotheroadplaneandparalleltoitsdirectionofmotion.1.3Thevaluesmeasuredrepresentthefrictionpropertiesobtainedwiththeequipmentandproceduresstatedinthistestmethodanddonotnecessarilyagreeorcorrelatedirectlywiththoseobtainedbyotherpavementfrictionmeasuringmethods.1.4Thevaluesareintendedforusein:1.4.1Evaluatingthebrakingfrictionforcesonapavementrelativetothatofotherpavements.1.4.2Evaluatingchangesinthebrakingfrictionforcesofaparticularpavementwiththepassageoftime.1.4.3Evaluatingthechangesinthebrakingfrictionforceofapavementwhensubjectedtopolishingwearandlossofmacrotexturecausedbytrafficwithpassageoftime.1.4.4Evaluatingchangesinthebrakingfrictionforcesofapavementcontaminatedwithice,moderateamounts2ofslushandsnow,pollen,vehicleoilspillsandcondensatesfromvehicleengineexhaust,anddepositsfromotherpollutionsources.1.4.5Evaluatingthebrakingfrictionforcesofaspecimentireonacleanorcontaminatedpavement.1.5Thefrictionvaluesreportedbythistest...
