Designation:E1960−07(Reapproved2015)StandardPracticeforCalculatingInternationalFrictionIndexofaPavementSurface1ThisstandardisissuedunderthefixeddesignationE1960;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1ThispracticecoversthecalculationoftheInternationalFrictionIndex(IFI)fromameasurementofpavementmacro-textureandwetpavementfriction.TheIFIwasdevelopedinthePIARCInternationalExperimenttoCompareandHarmo-nizeTextureandSkidResistanceMeasurements.Theindexallowsfortheharmonizingoffrictionmeasurementswithdifferentequipmenttoacommoncalibratedindex.Thisprac-ticeprovidesforharmonizationoffrictionreportingfordevicesthatuseasmoothtreadtesttire.1.2TheIFIconsistsoftwoparametersthatreportthecalibratedwetfrictionat60km/h(F60)andthespeedconstantofwetpavementfriction(Sp).1.3Themeanprofiledepth(MPD)hasbeenshowntobeusefulinpredictingthespeedconstant(gradient)ofwetpavementfriction.21.4Alineartransformationoftheestimatedfrictionat60km/hprovidesthecalibratedF60value.Theestimatedfrictionat60km/hisobtainedbyusingthespeedconstanttocalculatetheestimatedfrictionat60km/hfromameasurementmadeatanyspeed.1.5ThevaluesstatedinSI(metric)unitsaretoberegardedasstandard.Theinch–poundequivalentsarerationalized,ratherthanexactmathematicalconversions.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifanyassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:3E867TerminologyRelatingtoVehicle-PavementSystemsE1911TestMethodforMeasuringPavedSurfaceFrictionalPropertiesUsingtheDynamicFrictionTesterE1845PracticeforCalculatingPavementMacrotextureMeanProfileDepth2.2ISOStandard:DIS13473-1Acoustics–CharacterizationofPavementTex...
