ASTM_E_1845_-_15.pdf

Designation:E184515Standard Practice forCalculating Pavement Macrotexture Mean Profile Depth1This standard is issued under the fixed designation E1845;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 practice covers the calculation of mean profiledepth from a profile of pavement macrotexture.1.2 The mean profile depth has been shown to be useful inpredicting the speed constant(gradient)of wet pavementfriction.21.3 A linear transformation of the mean profile depth canprovide an estimate of the mean texture depth measuredaccording to Test Method E965.1.4 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:3E178 Practice for Dealing With Outlying ObservationsE965 Test Method for Measuring Pavement MacrotextureDepth Using a Volumetric Technique2.2 ISO Standard:ISO 13473-1AcousticsCharacterization of PavementTexture using Surface ProfilesPart 1:Determination ofMean Profile Depth43.Terminology3.1 Definitions:3.1.1 baselength,nlength of a segment of a pavementmacrotexture profile being analyzed,required to be 100 mm inthis practice.3.1.2 estimated texture depth(ETD),nestimate of themean texture depth(MTD),by means of a linear transforma-tion of the mean profile depth(MPD).3.1.3 mean profile depth(MPD),naverage of all the meansegment depths of all of the segments of the profile.3.1.4 mean segment depth,naverage value of the profiledepth of the two halves of a segment having a given base-length.3.1.5 mean texture depth(MTD),nmean depth of thepavement surface macrotexture determined by the volumetrictechnique of Test Method E965.3.1.6 profile depth(PD),ndifference between the ampli-tude measurements of pavement macrotexture and a horizontalline through the top of the highest peak within a givenbaselength.4.Summary of Practice4.1 This practice uses a measured profile of the pavementmacrotexture.4.2 The measured profile is divided for analysis purposesinto segments each having a baselength of 100 mm.The slope,if any,of each segment is suppressed by subtracting a linearregression of the segment.The segment is further divided inhalf and the height of the highest peak in each half segment isdetermined.The difference between that height and the averagelevel of the segment is calculated.The average value of thesedifferences for all segments making up the measured profile isreported as the MPD.5.Significance and Use5.1 This practice is suitable for the calculation of theaverage macrotexture depth from profile data.The results ofthis calculation(MPD)have proven to be useful in theprediction of the speed dependence of wet pavement friction.25.2 The MPD can be used to estimate the result of ameasurement of macrotexture depth using a volumetric tech-nique according to Test Method E965.The values of MPD and1This practice is under the jurisdiction of Committee E17 on Vehicle-PavementSystems and is the direct responsibility of Subcommittee E17.23 on SurfaceCharacteristics Related to Tire Pavement Slip Resistance.Current edition approved May 1,2015.Published June 2015.Originallyapproved in 1996.Last previous edition approved in 2009 as E1845 09.DOI:10.1520/E1845-15.2Wambold,J.C.,Antle,C.E.,Henry,J.J.,and Rado,Z.,International PIARCExperimenttoCompareandHarmonizeTextureandSkidResistanceMeasurements,Final report,Permanent International Association of Road Con-gresses(PIARC),Paris 1995.3For 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 International Organization for Standardization(ISO),1,ch.dela Voie-Creuse,Case postale 56,CH-1211,Geneva 20,Switzerland,http:/www.iso.ch.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 MTD differ due to the finite size of the glass spheres used in thevolumetric technique and because the MPD is derived from atwo-dimensional profile rather than a three-dimensional sur-face.Therefore a transformation equation must be used.5.3 This practice may be used with pavement macrotextureprofiles taken on actual road surfaces or from cores orlaboratory prepared samples.5.4 Aggregate size,shape,and distribution are featureswhich are not addressed in this practice.This practice is notmeant to provide a complete assessment of t