1、Designation: E2157 09Standard Test Method forMeasuring Pavement Macrotexture Properties Using theCircular Track Meter1This standard is issued under the fixed designation E2157; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar 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 procedure for obtaining andanalyzing pavement macrotexture profiles using the Circul
3、arTrack Meter (CTMeter).1.2 The CTMeter consists of a charge coupled device(CCD) laser displacement sensor that is mounted on an armthat rotates such that the displacement sensor follows a circulartrack having a diameter of 284 mm.1.3 The CTMeter is designed to measure the same circulartrack that is
4、 measured by the Dynamic Friction Tester(DFTester).1.4 The CTMeter can be used both for laboratory investi-gations and in the field on actual paved surfaces.1.5 The software developed for the CTMeter reports themean profile depth (MPD) and the root mean square (RMS)values of the macrotexture profile
5、s.1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 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 ap
6、pro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E867 Terminology Relating to Vehicle-Pavement SystemsE1845 Practice for Calculating Pavement MacrotextureMean Profile DepthE1911 Test Method for M
7、easuring Paved Surface FrictionalProperties Using the Dynamic Friction Tester2.2 Other Document:Manufacturers “Operating Manual for the Circular TextureMeter,” Sunny Koken Company, 3-8-4 Shinsayama,Sayama-shi, Saitama-ken, Japan 13313. Terminology3.1 See Terminology E867.3.2 Definitions:3.2.1 negati
8、ve texture, nmacrotexture produced by de-pressions in the surface.3.2.2 positive texture, nmacrotexture produced by asperi-ties projecting above the surface.4. Summary of Test Method4.1 This test method uses a displacement sensor that ismounted on an arm that rotates clockwise at a fixed elevationfr
9、om the surface being measured. The sensor is attached to thearm at a radius of 142 mm.4.2 The device is controlled by a notebook computer thatsaves and processes the data. When the measurement isinitiated by the computer, a DC motor drives the arm for a full360 revolution.4.3 The profile is recorded
10、 in the computer memory anddivided into eight segments for analysis (See Fig. 1). Thecomputer software can process the data to report either theMPD in accordance with Practice E1845 or the RMS or bothfor each segment.5. Significance and Use5.1 In the PIARC International Experiment (1)3it wasfound th
11、at the volumetric mean texture depth (MTD) washighly correlated to the speed constant of the InternationalFriction Index. It has been found that the average of the MPDvalues for the eight segments using the CTMeter is extremelyhighly correlated with the MTD and can replace the volumetricmeasurement
12、for determination of the MTD (2). The recom-mended relationship for the estimate of the MTD from theMPD by the CTMeter is:MTD 5 0.947 MPD 1 0.069 (1)Where MTD and MPD are expressed in millimetres.1This test method is under the jurisdiction of ASTM Committee E17 on Vehicle- Pavement Systems and is th
13、e direct responsibility of Subcommittee E17.23 onSurface Characteristics Related to Tire Pavement Slip Resistance.Current edition approved Nov. 1, 2009. Published December 2009. Originallyapproved in 2001. Last previous edition approved in 2005 as E2157 01 (2005).DOI: 10.1520/E2157-09.2For reference
14、d 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.3The boldface numbers given in parentheses refer to a list of references at
15、 theend of the text.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 1These equations differ from those given in Practice E1845,which are for the estimated texture depths from linear profiles.5.2 Comparison of the MPD and the RMS
16、 for a surfaceprovides information of the nature of the texture, that is,whether the texture is positive or negative (3).5.3 Analysis of the individual segments can be performed toexamine the profile parallel to the direction of travel (SegmentsAand E) and perpendicular to the direction of travel (S
17、egmentsC and G). This information could be particularly useful in thestudy of surfaces that have texture with significant directionalcharacteristics.6. Apparatus6.1 CTMeterThe measuring instrument consists of a CCDlaser-displacement sensor mounted on an arm that rotates at 80mm above the surface on
18、a diameter of 284 mm. The arm isdriven by a DC motor at a tangential velocity of 6 m/min in acounterclockwise direction.6.2 Data CollectionThe CCD is sampled 1024 times perrevolution providing a sample spacing on 0.87 mm by an A/Dconverter.6.3 Data RecordingThe data are recorded in memory in anotebo
19、ok computer. The data are segmented into eight 111.5mm arcs of 128 samples each. The computer software com-putes the MPD or the RMS, or both, of each segment.6.4 Displacement SensorThe CCD laser-displacementsensor shall have a spot size of 70 m over a range of 65 to 90mm. The vertical resolution sha
20、ll be 3 m.7. Test Samples7.1 FieldField test surfaces shall be free of loose par-ticles. The test surface does not have to be horizontal providedthe instrument can be leveled in working position.7.2 LaboratoryLaboratory test panels shall be clean andfree of loose particles and shall be held firmly d
21、uring measure-ment.7.2.1 Flat laboratory test panels shall have a test surface ofat least 600 by 600 mm with no disturbance from edge effectsfor a diameter of 500 mm.8. CalibrationNOTE 2Manufacturers CalibrationThe CTMeter shall be cali-brated at the manufacturers facility, using a precision machine
22、d calibra-tion surface having a sawtooth profile having an amplitude of 7 mm anda period of 28 mm, producing an MPD of 3.5 mm.8.1 Field CalibrationBefore each measurement session,the CTMeter shall be checked using the calibration panelprovided by the manufacturer. The result shall be within 60.05mm
23、of the value indicated on the panel. If the result is outsidethese limits, the CTMeter shall be returned to the manufacturerfor calibration.9. Procedure9.1 Place the CTMeter on the test surface that should be freeof any contamination. If the measurement is to be used inconjunction with a measurement
24、 by the Dynamic FrictionTester (DFTester) specified in Test Method E1911, the locationshould be marked such that the DFTester can be placed in thesame location.NOTE 3It is preferable to operate the CTMeter at a location where thesurface is flat. However, it has been shown that the effect is negligib
25、le fora deviation from flatness of up to 6 mm over a 0.5 m specimen.9.2 Orient the CTMeter with the Segments C and G perpen-dicular to the direction of travel as shown in Fig. 1.NOTE 4If there is no predominant travel direction, position theCTMeter in an identifiable orientation, such as a physical
26、characteristic ofthe site or according to compass direction.9.3 Select the option to compute the MPD or the RMS, orboth, of the profiles and initiate the measurement from thenotebook computer.9.4 Record the test results or store the data for futureanalysis.10. Report10.1 The report shall include the
27、 following:10.1.1 Date and time of day;10.1.2 Individual values of the friction MPD or the RMS, orboth, for each of the eight segments and the average value ofthe eight segments;10.1.3 Temperature of the test surface;10.1.4 Type, age, condition, and location of test surface;10.1.5 Plot of the profil
28、e; and10.1.6 Type and date of the most recent calibration.11. Precision and Bias11.1 PrecisionThe standard deviation of eight measure-ments on the same test surface is 0.03 mm.11.2 BiasThere is no basis for determination of the bias.FIG. 1 Segments of the Circular Track ProfileE2157 09212. Keywords1
29、2.1 pavement texture; skid resistanceAPPENDIX(Nonmandatory Information)X1. DIMENSIONS OF THE CIRCULAR TRACK TMETERFig. X1.1 depicts the dimensions of the CTMeter.E2157 093FIG. X1.1 Dimensions of the CT MeterE2157 094REFERENCES(1) Wambold, J. C., Antle, C. E., Henry, J. J., and Rado, Z., “Internation
30、alPIARC Experiment to Compare and Harmonize Texture and SkidResistance Measurements, Final report,” Permanent InternationalAssociation of Road Congresses (PIARC), Paris, 1995.(2) Abe, H., Henry, J.J., Tamai, A., and Wambold, J.C., “Measurement ofPavement Macrotexture Using the Circular Texture Meter
31、 (CTMeter),”Transportation Research Board Annual Meeting, Washington DC,2001.(3) Wennink, M. and Gerritsen, W., “Detection of Changes of PavementTexture Material Recognition,” Proceedings of the Fourth Interna-tional Symposium on Pavement Surface Characteristics, Nantes, 2000.ASTM International take
32、s no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own res
33、ponsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be address
34、ed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the
35、 address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).E2157 095
