1、Designation: D 2493 01e1StandardViscosity-Temperature Chart for Asphalts1This standard is issued under the fixed designation D 2493; 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
2、 indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.e1NOTEAdjunct references were corrected editorially in April 2006.1. Scope1.1 The viscosity-temperature chart covered by this stan-dard is a convenient means of plotti
3、ng data for estimating theviscosity of asphalts at any temperature within a limited range.Conversely, the chart may be used to ascertain the temperatureat which a desired viscosity is attained.1.2 The chart is suitable for original asphalt cements and forasphalts recovered from laboratory aging test
4、s or extractedfrom pavements.1.3 The chart is based on a viscositytemperature relation-ship that can be plotted using any appropriate set of units. Forconvenience, charts based on both conventional and SI unitsare provided.1.4 The range of the chart is sufficient for roofing asphalts.1.5 The range o
5、f the chart is sufficient for liquid asphalts(bitumens) whose viscosity exceeds 0.1 poise (10 centipoise).2. Referenced Documents2.1 ASTM Standards:2D 341 Test Method for Viscosity-Temperature Charts forLiquid Petroleum ProductsD 2170 Test Method for Kinematic Viscosity of Asphalts(Bitumens)D 2171 T
6、est Method for Viscosity of Asphalts by VacuumCapillary ViscometerD 3205 Test Method for Viscosity ofAsphalt with Cone andPlate Viscometer3D 4957 Test Method for Apparent Viscosity of AsphaltEmulsion Residues and Non-Newtonian Bitumens byVacuum Capillary Viscometer32.2 ASTM Adjuncts:Viscosity-Temper
7、ature Chart forAsphalts (17 by 18 in. padof 25 sheets)43. Significance and Use3.1 The viscosity-temperature chart is a convenient meansof plotting the viscosity data for estimating the viscosity ofasphalts, recovered asphalts, and roofing asphalts at anytemperature within a limited range. It is also
8、 a convenientmeans to estimate the temperature at which a desired viscosityis attained.3.2 Kinematic viscosity-temperature charts are described inCharts D 341.4. Description4.1 For Fig. 1, the chart coordinates are logarithm of thelogarithm of the viscosity in centipoise as the ordinate, andlogarith
9、m of the absolute temperature in Degrees Rankine(degrees F + 459.7) as the abscissa. However, the viscosity inpoise and the temperature in degrees Fahrenheit is shown in thechart for convenience.44.1.1 The range of the chart is 101to 1024poise and 0 to400F, as shown in Fig. 1. Its size is 16 by 17 i
10、n. (406 by 432mm).4.2 For Fig. 2, the chart coordinates are logarithm of thelogarithm of the viscosity in mPa.s as the ordinate, andlogarithm of the absolute temperature in degrees Kelvin(degrees C + 273.2) as the abscissa. However, viscosity inPascal-seconds, and the temperature in degrees Celsius
11、isshown in the chart for convenience.1 Pa.s 5 mPa.s 3 103! (1)4.2.1 The range of the chart is 102to 1023Pa.s and 20 to200C, as shown in Fig. 2.4.3 The temperature range of the charts may be extended tolower temperatures by renumbering the temperature scale of asecond chart, according to Table 1, dis
12、carding the portionabove 230F (110C), and placing the 230F (110C) axisalong the 0F (-17.8C) axis of an original chart.1This chart is under the jurisdiction of ASTM Committee D04 on Road andPaving Materials and is the direct responsibility of Subcommittee D04.44 onRheological Tests.Current edition ap
13、proved Dec. 10, 2001. Published March 2002. Originallyapproved in 1966. Last previous edition approved in 1995 as D 2493 95a.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
14、refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Available from ASTM International Headquarters. Order Adjunct No.ADJD2493.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Procedure5.1 For temperatures ab
15、ove 60C (140F), plot twoviscosity-temperature points and carefully draw a straight linethrough the points. Plot at least three viscosity-temperaturepoints if the included temperature range is below 60C(140F). Carefully draw a straight line or curve through thepoints.Apoint on this line, within the t
16、emperature range of thepoints plotted, shows the viscosity at the corresponding desiredtemperature.NOTE 1These charts are appropriate for use at higher temperatures,where asphalts are primarily viscous.At lower temperatures most asphaltsbecome viscoelastic. When this occurs, viscosity alone is insuf
17、ficient todescribe an asphalts flow properties. Most asphalts are primarily viscousat temperatures above 60C (140F). Caution should be used whenapplying this standard below that temperature.5.2 Some asphalts have viscosity-temperature relationshipstoo complex to be represented by only three points,
18、as shownin Fig. 1. In this case determine the viscosity at sufficienttemperatures to produce a curve adequate for the purposeintended.5.3 If the viscosities are not known they should be deter-mined in accordance with Test Methods D 2170, D 2171,D 3205, and D 4957. Viscosities determined at temperatu
19、resother than the temperatures specified in each of these testmethods may be used.5.4 Viscosities determined by extrapolation of data may beunreliable.5.5 The viscosity values represented by the data points mayhave been obtained at different shear rates. This chart does notreflect the shear rate at
20、which the viscosities were determined.6. Keywords6.1 asphalt; rheology; viscosity; viscosity-temperature chartFIG. 1 Facsimile of Viscosity-Temperature Chart on Which a Typical Experimental Curve Has Been PlottedD249301e12FIG. 2 Viscosity-Temperature Chart for Asphalts on Which a Typical Experimenta
21、l Curve has Been PlottedTABLE 1 Low-Temperature SubstitutesNOTE 1Standards for determining the viscosity of asphalts at verylow temperatures have not been developed. The significance of extrapo-lated viscosities at very low temperatures is not known.Column A Column BTemperature Printed on Chart, F (
22、C) Low-Temperature Substitute, F (C)+ 170 (76.7) 40 (40)+ 185 (84.9) 30 (34.4)+ 200 (93.3) 20 (28.9)+ 215 (102.8) 10 (23.3)+ 230 (110.0) 0 (17.8)D249301e13APPENDIX(Nonmandatory Information)X1. SUGGESTIONS FOR DATA ANALYSISX1.1 The chart in Fig. 1 includes the region where theviscosity of asphalts de
23、pends not only on the temperature, butalso on the shearing conditions. Therefore, the data plotted onthe viscosity-temperature chart must be obtained under stan-dardized shearing conditions, for example, at the same shearrate, or the same shear stress. Constant shearing conditions alsoimplies the us
24、e of the same viscometer, or viscometers of thesame type and size, to avoid differences in viscosity valuescaused by differences in the extent of breakdown of themicellar structure of the asphalt due to shearing in themeasurement process.X1.2 Asphalt viscosities are often reported at an arbitraryshe
25、ar rate of 0.05 s1. Interpolation or extrapolation of mea-sured viscosity data is often required to obtain values for thisshear rate. A useful model for interpolating or extrapolatingasphalt rheological measurements is the empirical “PowerLaw” relationship:t5h1gc(X1.1)where:t = the shearing stress,g
26、 = the rate of shear,h1= the apparent viscosity at a shear rate of 1 s1, andc = the slope of a plot of log t versus log g .The parameter c is called the Complex Flow Index, and is anindicator of the rheological character of the material. ForNewtonian liquids, whose viscosity does not vary with shear
27、rate, c =1. If c 1, the apparent viscosityincreases with shear rate.X1.3 Because a small error in the value of c can cause alarge error in an extrapolated viscosity value, it is recom-mended that the Power Law slope be determined usingreplicate tests on the material. The average value of c can bedet
28、ermined by regression analysis of the log t versus log gdata. If the data for replicate tests do not superimpose on a plotof all the data on the same chart, the calibration and operatingprocedure for the viscometer should be checked before pro-ceeding further with the data analysis. If there are a s
29、mallnumber of outliers, these can be discarded, and the remainderof the data used in the regression analysis. Fig. X1.1 shows anexample of data containing outliers that should be ignored.X1.3.1 The objective of screening for outliers should be toretain all data that legitimately belong in the popula
30、tion ofresults characteristic of the test method used, and to eliminateonly those that differ so drastically that their inclusion distortsthe shear stress versus shear rate relationship. Therefore, thecriterion for rejecting data should be conservative. If a statis-tical technique is used, the signi
31、ficance level of the test shouldbe no greater than one percent.X1.4 Large extrapolations of rheological data to obtainvalues at constant shear rate are often unavoidable becausemost viscometers allow a limited range of shear stress, and thelarge variation in viscosity over a range of temperatures re
32、sultsin large differences in observed shear rate at different testtemperatures. A procedure which circumvents this problem isto plot the apparent viscosity at constant power input per unitvolume as a function of temperature. This avoids long extrapo-lations of the shear stress/shear rate relationshi
33、ps. H. E.Schweyer and others have recommended that apparent viscosi-ties at a constant power input of 100 W/m3be used. However,this value has no theoretical significance, and may not beappropriate for all viscometers. A value which minimizes theamount of extrapolation needed to estimate the apparent
34、viscosities in the temperature range of interest should beselected.X1.5 To estimate the apparent viscosity at constant powerinput, first determine the Power Law constants h1and c froma plot or regression analysis of log shear stress versus log shearrate. Calculate the apparent viscosity at power inp
35、ut P from:hP5h1 FPh1Gc 2 1c 1 1(X1.2)where:hP= apparent viscosity, Pa.s at power input P, W/m3,h1= apparent viscosity, Pa.s at 1 s1shear rate, andc = complex flow index.X1.6 The effect of temperature on apparent viscosity can beshown by plotting the constant power input viscosities at twoor more tem
36、peratures on the chart in Fig. 1. Because of thenon-linearity of the scales on this chart, the viscosities must beplotted in the units shown. Many asphalts will have a straightline viscosity versus temperature relationship on the chart.However, a minimum of 3 points should be plotted, to ensurethat
37、the nature of the relationship is shown. Because of thepossibility of curvature, particularly at very high viscositylevels, extrapolation is not recommended.X1.7 Alternatively, a regression analysis of log log h versuslog T (absolute temperature) can be performed. To be consis-tent with Fig. 1, the
38、viscosity values must be converted tomPa.s or cP before taking the logarithms. A straight regressionline of this type is shown in Fig. X1.2.X1.8 Lefebvre and Robertson5is suggested for additionalreading, because it describes the application of these tech-niques.5Lefebvre, J. A. and Robertson, W. D.,
39、 “Viscosity Characteristics of TwoCanadian Asphalts,” Proceedings CTAA 15, Vol 101, 1970.D249301e14ASTM International takes 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 deter
40、mination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.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
41、withdrawn. Your comments are invited either 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
42、 your comments have not received a fair 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 (
43、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).FIG. X1.1 Power Law Shear Stress versus Shear RateRelationshipFIG. X1.2 Viscosity versus Temperature RelationshipD249301e15
