1、Designation: D7741 11Standard Test Method forMeasurement of Apparent Viscosity of Asphalt-Rubber orOther Asphalt Binders by Using a Rotational Hand HeldViscometer1This standard is issued under the fixed designation D7741; the number immediately following the designation indicates the year oforiginal
2、 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 The use of high viscosity asphalt binders like Asphalt-Rubber is be
3、coming more common in the United States andworldwide. Specifications such as Specification D6114 note theneed for field control of the apparent viscosity and require theuse of a field production rotational viscometer. The testing ofAsphalt-Rubber Binder for use in Asphalt- Rubber Hot Mixand for Asph
4、alt-Rubber Membrane is necessary to ensureconsistent mix properties that will ensure good performance ofthese materials. Logistics of field applications limits the use ofconventional laboratory controls and testing equipment. Thistest, using a hand held rotational viscometer can be conductedin eithe
5、r the field or laboratory to determine the apparentviscosity of Asphalt-Rubber and other high viscosity bindersfor field production control and to assess the uniformity of thebinder produced or for other related purposes.1.2 Asphalt-Rubber Binder consists of a blend of pavinggrade asphalt cement and
6、 crumb rubber as described inSpecification D6114. Other high viscosity asphalt binders mayconsist of asphalts modified with polymer or fiber or both.Testing is performed following the specified reaction time, ifany, within the production process. Control of the raw materi-als is separate from the te
7、st.1.3 The values stated in SI units or inch-pound units are tobe regarded separately as standard. The values stated in eachsystem may not be exact equivalents; each system shall be usedindependently of the other. Combining values from the twosystems may result in non-compliance with the standard.1.
8、4 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 Doc
9、uments2.1 ASTM Standards:2D6114 Specification for Asphalt-Rubber Binder3. Significance and Use3.1 This test is primarily used for field production control ofAsphalt-Rubber (A-R) and other high viscosity binders; how-ever the test can also be used in a laboratory setting.3.2 Ahand held rotational vis
10、cometer is used to measure theapparent viscosity of a completed blend of A-R or highviscosity binder. A rotor (spindle), turning at constant speed, isinserted in the liquid binder to be measured. The resistance tomovement of the spindle (torque) caused by the viscosity of thesurrounding liquid is me
11、asured using a special mechanism toobtain direct readings in Pas or cP.NOTE 1Spindle generally made of stainless steel, although anothermetal such as brass could be used.3.3 The measured apparent viscosity is used to control theproduction of the A-R or other high viscosity binder, to assessthe unifo
12、rmity of the binder produced or for other relatedpurposes.3.4 As the spindle turns in the A-R or other high viscositybinder, it has a tendency to “drill” into the sample (i.e., forA-R,the spindle spins the rubber particles out of the measurementarea). Consequently, the apparent viscosity drops to re
13、flect onlythe liquid phase of the high viscosity binder. Therefore, thepeak viscosity measurement value is recorded to reflect theviscosity of the blended material.4. Apparatus4.1 Viscometerhand held rotational type viscometer (seeFig. 1). The viscometer shall be equipped with a level bubbleto ensur
14、e proper orientation of the viscometer in the sample to1This 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, 2011. Published January 2012. DOI: 10.1520
15、/D7741112For 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.1Copyright ASTM International, 100 Barr Harbor Drive,
16、 PO Box C700, West Conshohocken, PA 19428-2959, United States.be tested. Spindle (rotor) speed typically 62.5 rpm, howevermay vary with different manufacturers.4.2 Spindle (Rotor)Diameter - 24 6 1.1 mm. 1.0 6 0.05inch; Height - 53 6 0.1 mm 2 6 .005 inch or equivalent (seeFig. 2).4.3 ThermometerDigit
17、al with metal jacket probe, 1 de-gree C 2 degree F precision.4.4 Sample Can4 liter 1 gallon metal can with wire bale.4.5 Viscosity Standard OilsCalibrated in absolute viscos-ity in Pas centipoises cP and in the range of 1.0 to 5.0 Pas1000 to 5000 cP.4.6 Controllable heat source, such as a hot plate,
18、 gas stoveor burner, etc., to maintain the test temperature of the A-R orhigh viscosity binder sample during viscosity measurement.4.7 Viscometer holderclean metal can or some type offrame where the viscometer can be stored between tests.5. Calibration Verification5.1 Calibration of the rotational v
19、iscometer shall be verifiedprior to use at each site per manufacturers instructions usingthe reference viscosity standard oils.6. Sampling6.1 The sample shall consist of at least 3 liters 0.75 gal ofthe completed mixture of A-R or other high viscosity binder.Obtain the sample from an appropriate sam
20、ple valve located tointercept the normal flow of material during production.Perform sampling and testing in close proximity to the plantoperation to avoid undue temperature loss during handling.FIG. 1FIG. 2D7741 1126.2 Prior to sampling, draw at least 3 liters 0.75 gal fromthe sampling valve and dis
21、card. Then open the sample valveand draw approximately 3 liters 0.75 gal into a new, cleansample can for testing.7. Test and sampling procedure7.1 As immediately as practical place the sample containerwith the drawn sample on a smooth, level support for finalpreparation and testing. Set the open sam
22、ple container on orover the controllable heat source as appropriate7.2 Manually stir the sample using an appropriate metal stirrod to prevent scorching or burning. Use of the temperatureprobe for stirring is permitted.7.3 Continue stirring until a consistent specified test tem-perature is achieved.
23、The test temperature shall be within62C 65F of the specified test temperature. The actual testtemperature shall be recorded with viscosity data. Typical testtemperatures are 175C 350F or 190 C 375F, or asspecified.7.4 Insert the viscometer spindle, without plugging the ventholes of the spindle, into
24、 the hot A-R or other high viscositybinder near the edge of the sample container for about 1 minuteto equilibrate to the sample temperature. Then move it to thetest location, approximately at the center of the sample, tomake the viscosity measurement. Immerse the spindle in theA-R or other high visc
25、osity binder to the manufacturers depthmark on the connecting shaft. Use the level bubble to align thespindle perpendicular to the binder surface and level theviscometer.After immersing the viscometer spindle in the A-R or otherhigh viscosity binder at the test location for 5 to 10 seconds,engage th
26、e viscometer and take a viscosity measurement inaccordance with the manufacturers instructions. Record theviscometer peak measurement as the viscosity test reading. Thetime interval between stirring, immersion of the spindle andtesting shall be approximately 15 seconds, and in no casegreater than 20
27、 seconds. Three measurements shall be takenand averaged and reported as the viscosity. Between measure-ments the viscometer spindle should be moved away from thecenter (without removing it from the A-R or other highviscosity binder sample) and the sample should be thoroughlystirred again.7.5 To clea
28、n the spindle assembly, return the viscometer toholder with spindle suspended in a suitable solvent. Beforeusing the spindle again, wash off the solvent and dry thespindle to avoid solvent contamination of the next sample.8. Reporting of results8.1 Report the test date, test temperature in C or F to
29、 thenearest degree and each of the three test viscosities to thenearest 0.1 Pas or 100 cP. Also report the average of the threeviscosities to the nearest 0.1 Pas or 100 cP.NOTE 2other information may be reported such as; project nameand/or number, location of plant, material (A-R or other high visco
30、sitybinder), supplier, equipment model.9. Precision and Bias9.1 PrecisionAn Interlaboratory Asphalt-Rubber (A-R)Round Robin Study was conducted to develop the Precision ofthe test and detailed results of that study can be found inASTMReport Number D041039, entitled 9 Interlaboratory HandheldViscomet
31、er A-R Round Robin Study to Estimate the Precision(Repeatability and Reproducibility) of the Proposed ASTMStandard Handheld Viscometer Test Method9.3The study wasconducted in August 2010 on a construction project in thePhoenix, Arizona metropolitan area. For the purposes of thatstudy 12 one gallon c
32、ans of A-R were tested in the field usingthe handheld viscometer at 177 C 350 F in accordance withthe most current ASTM handheld viscometer draft testingstandard. The cans were labeled from 1 to 12 for purposes ofdistribution to five laboratories to conduct the same testconducted in the field with t
33、he same type of equipment. Twocans were selected at random and were delivered to each of thefive laboratories. Each laboratory reported the three viscositymeasurements that they took for each sample. From this testingalong with the three test measurements taken during construc-tion for all 12 sample
34、s, it was possible to develop the Precisionstatements for single operator and multi-laboratory.Single-Operator Precision Statement (Repeatability)Duplicate values by the same operator using the same testequipment in the shortest practical period of time shall beconsidered not equivalent if the diffe
35、rence in the two results,expressed as a percent of the mean, exceeds 12.0 %.Multi-laboratory Precision (Reproducibility)The values reported by each of two laboratories, representingthe arithmetic average of duplicate determinations, shall beconsidered not equivalent if they differ by more than 22.0
36、%.9.2 BiasNo information can be presented on the bias ofthe procedure in this test method for measuring viscositybecause no material having an accepted reference value isavailable.10. Keywords10.1 Asphalt-rubber; hand held rotational viscometer; vis-cosity3Supporting data have been filed at ASTM Int
37、ernational Headquarters and maybe obtained by requesting Research Report RR:D04-1039.D7741 113This 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 eit
38、her for revision of this standard or for additional standardsand should be addressed 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
39、hearing you shouldmake your views known to the ASTM Committee on Standards, at the 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 stand
40、ard 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/).D7741 114
