1、Designation: D 2726 05aStandard Test Method forBulk Specific Gravity and Density of Non-AbsorptiveCompacted Bituminous Mixtures1This standard is issued under the fixed designation D 2726; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method c
3、overs the determination of bulkspecific gravity and density of specimens of compacted bitu-minous mixtures.1.2 This test method should not be used with samples thatcontain open or interconnecting voids or absorb more than 2 %of water by volume, or both, as determined in 10.3.1.3 The values stated in
4、 SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.4 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 hea
5、lth practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 979 Practice for Sampling Bituminous Paving MixturesD 1188 Test Method for Bulk Specific Gravity and Densityof Compacted Bituminous Mixtures Using Paraffin-CoatedSpecime
6、nsD 3203 Test Method for Percent Air Voids in CompactedDense and Open Bituminous Paving MixturesD 3666 Specification for Minimum Requirements forAgen-cies Testing and Inspecting Road and Paving MaterialsD 4753 Specification for Evaluating, Selecting, and Speci-fying Balances and Standard Masses for
7、Use in Soil, Rock,and Construction Materials TestingD 5361 Practice for Sampling Compacted Bituminous Mix-tures for Laboratory TestingD 6752 Test Method for Bulk Specific Gravity and Densityof Compacted Bituminous Mixtures Using AutomaticVacuum Sealing Method3. Terminology3.1 Definitions of Terms Sp
8、ecific to This Standard:3.1.1 bulk densityas determined by this test method, themass of a metre cubed (or foot cubed) of the material at 25C(77F).3.1.2 bulk specific gravityas determined by this testmethod, the ratio of the mass of a given volume of material at25C to the mass of an equal volume of w
9、ater at the sametemperature.4. Summary of Test Method4.1 The specimen is immersed in a water bath at 25C(77F). The mass under water is recorded, and the specimen istaken out of the water, blotted quickly with a damp cloth towel,and weighed in air. The difference between the two masses isused to meas
10、ure the mass of an equal volume of water at 25C.4.2 This test method provides guidance for determination ofthe oven dry or thoroughly dry mass of the specimen. The bulkspecific gravity is calculated from these masses. Then thedensity is obtained by multiplying the specific gravity of thespecimen by
11、the density of the water.5. Significance and Use5.1 The results obtained from this test method can be usedto determine the unit weight of compacted dense bituminousmixtures and in conjunction with Test Method D 3203,toobtain percent air voids. These values in turn may be used indetermining the relat
12、ive degree of compaction.5.2 Since specific gravity has no units, it must be convertedto density in order to do calculations that require units. Thisconversion is made by multiplying the specific gravity at agiven temperature by the density of water at the same tempera-ture.1This test method is unde
13、r the jurisdiction of ASTM Committee D04 on Roadand Paving Materials and is the direct responsibility of Subcommittee D04.21 onSpecific Gravity and Density of Bituminous Mixtures.Current edition approved Sept. 15, 2005. Published September 2005. Originallyapproved in 1968. Last previous edition appr
14、oved in 2005 as D 272605.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appea
15、rs at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 1The personnel and equipment used in performing this test canbe evaluated in accordance with Practice D 3666.6. Apparatus6.1 Balance, with ample capac
16、ity, and with sufficient sensi-tivity to enable bulk specific gravities of the specimens to becalculated to at least four significant figures, that is, to at leastthree decimal places. It shall be equipped with a suitableapparatus to permit weighing the specimen while suspended inwater. To avoid err
17、oneous readings by undue displacement ofwater, use wire or fish line of the smallest practical size tosuspend the specimen and holder. Do not use chains, strings, orsash cords. The balance shall conform to Specification D 4753as a Class GP2 balance.NOTE 2Since there are no more significant figures i
18、n the quotient(bulk specific gravity) than appear in either the dividend (the mass of thespecimen in air) or in the divisor (the mass of the volume of water equalto the volume of the specimen, obtained from the difference in weight ofthe saturated surface-dry specimen in air and in water), this mean
19、s that thebalance must have a sensitivity capable of providing both mass values toat least four figures. For example, a sensitivity of 0.1 g would provide foursignificant figures for mass in the range from 100.1 g to 999.9 g.6.2 Water Bath, capable of maintaining a temperature of 256 1C (77 6 1.8F)
20、for immersing the specimen in water whilesuspended, equipped with an overflow outlet for maintaining aconstant water level. The use of an overflow outlet is manda-tory.NOTE 3The water bath does not need to be a sophisticated device.Any method that maintains 25C 6 1C can be used including tempering,a
21、quarium heaters, stirrers, or other devices.7. Sampling7.1 Specimens may be either laboratory-molded bituminousmixtures or from bituminous pavements.7.2 Obtain field samples in accordance with Practice D 979.7.3 Pavement specimens shall be taken from pavementswith a core drill, diamond or a carborun
22、dum saw, or by othersuitable means, in accordance with Practice D 5361.8. Test Specimens8.1 Size of SpecimensIt is recommended, (1) that thediameter of cyclindrically molded or cored specimens, or thelength of the sides of sawed specimens, be at least equal to fourtimes the maximum size of the aggre
23、gate; and (2) that thethickness of specimens be at least one and one half times themaximum size of the aggregate.8.2 Care shall be taken to avoid distortion, bending, orcracking of specimens during and after removal from pave-ments or mold. Specimens shall be stored in a safe, cool place.8.3 Specime
24、ns shall be free of foreign materials such as sealcoat, tack coat, foundation material, soil, paper, or foil. Whenany of these materials are visually evident, they shall beremoved by sawing in accordance with 8.6.8.4 If desired, specimens may be separated from otherpavement layers by sawing or other
25、 satisfactory means.9. Procedure9.1 For Cores and for Other Specimens that May ContainMoisture or SolventOnly specimens that are known to bethoroughly dry (that is, laboratory-prepared dried specimens),are to be tested in accordance with 9.2. All others are assumedto contain moisture or solvent and
26、are to be tested in accor-dance with 9.1. The sequence of testing for 9.1 is: in water,saturated-surface dry, dry.9.1.1 Mass of Specimen in WaterCompletely submergethe specimen in the water bath at 25 6 1C (77 6 1.8F) for3 to 5 min then determine the mass by weighing in water.Designate this mass as
27、C. If the temperature of the specimendiffers from the temperature of the water bath by more than2C (3.6F), the specimen shall be immersed in the water bathfor 10 to 15 min, instead of 3 to 5 min.9.1.2 Mass of Saturated Surface-Dry Specimen in AirSurface dry the specimen by blotting quickly with a da
28、mp clothtowel and then determine the mass by weighing in air.Designate this mass as B.9.1.3 After determining the mass in water and in a saturated-surface dry condition, thoroughly dry the specimen to aconstant mass at 110 6 5C (230 6 9F). Allow the specimento cool and weigh in air. Designate this m
29、ass as A. Othermethods may be used to dry the specimen as long as a constantmass is achieved (mass repeats within 0.1 %).NOTE 4Drying the specimen at the required temperature of 110C(230F) will change the characteristics and shape of the specimen. Thiswill make the specimen unsuitable for further te
30、sting. Drying thespecimen at a reduced temperature such as 52C (125F), in order to keepit intact, will not meet the requirements of this test method.9.1.3.1 Microwave drying or other approved methods maybe used to dry the specimen if the specimen is not over-heatedand documentation exists showing th
31、at the results are equiva-lent to oven drying. The interval of time between readings todetermine constant mass must be sufficient to ensure that allmoisture and solvent has been removed. This interval isdependent on the size of the specimen and can be determinedby experimentation and confirmed with
32、the oven-dried com-parisons. Documentation must exist to validate the intervals.9.2 For Laboratory-Prepared Thoroughly Dry Specimens:9.2.1 Mass of Dry Specimen in AirDetermine the mass byweighing the specimen after it has been standing in air at roomtemperature for at least 1 h. Designate this mass
33、as A.9.2.2 Mass of Specimen in WaterUse the same procedureas described in 9.1.1.9.2.3 Mass of Saturated Surface-Dry Specimen in AirSurface dry the specimen by blotting quickly with a damp clothtowel and then determine the mass by weighing in air.Designate this mass as B.10. Calculation10.1 Calculate
34、 the bulk specific gravity of the specimen asfollows:Bulk sp gr 5 A/B 2 C! (1)where:A = mass of the dry specimen in air, g,(BC) = mass of the volume of water for the volume ofthe specimen at 25C,B = mass of the saturated surface-dry specimen in air,g, andD 2726 05a2C = mass of the specimen in water,
35、 g.10.2 Calculate the density of the specimen as follows:Density 5 Bulk sp gr 3 997.0 or 62.24! (2)where:997.0 = density of water in kg/m3at 25C (0.9970 g/cm3)10.3 Calculate the percent water absorbed by the specimen(on volume basis) as follows:Percent water absorbed by volume 5B 2 AB 2 C3 100 (3)10
36、.4 If the percent water absorbed by the specimen in 10.3exceeds 2 %, use Test Method D 1188 or Test Method D 6752.10.5 This test method has been written expressing density inkilograms per cubic metre. Conversion to express the densityin pounds per cubic foot is acceptable.11. Report11.1 Report the f
37、ollowing:11.1.1 Bulk specific gravity of the mixture to the thirddecimal place as: bulk specific gravity at 25C,11.1.2 Density of the mixture with four significant figures inkg/m3or lb/ft3as: density at 25C,11.1.3 Type of mixture,11.1.4 Size of sample, and11.1.5 Water absorption, %.12. Precision and
38、 Bias12.1 Precision:12.1.1 Single Operator PrecisionThe single operatorstandard deviations (1s limits) for specimens prepared inaccordance with 9.2, for mixtures containing aggregate withabsorption of less than 1.5 %, are shown in Table 1. The resultsof two properly conducted tests on the same mater
39、ial, by thesame operator, using the same equipment, should be consid-ered suspect if they differ by more than the d2s single operatorlimits shown in Table 1.12.1.2 Multilaboratory PrecisionThe multilaboratorystandard deviations (1s limits) for specimens prepared inaccordance with 9.2, for mixtures c
40、ontaining aggregate withabsorption of less than 1.5 %, are shown in Table 1. The resultsof two properly conducted tests on the same material, bydifferent operators, using different equipment, should be con-sidered suspect if they differ by more than d2s multilaboratorylimits shown in Table 1.12.2 Bi
41、asNo information can be presented on the bias ofthe procedure because no material having an accepted refer-ence value is available.13. Keywords13.1 air voids; compaction; density; specific gravity; unitweightSUMMARY OF CHANGESCommittee D04 has identified the location of selected changes to this stan
42、dard since the last version(D 2726 05) that may impact the use of this standard. (Approved Sept. 15, 2005.)(1) Added Summary of Changes.Committee D04 has identified the location of selected changes to this standard since the last version (D 2726 04) that mayimpact the use of this standard. (Approved
43、 July 15, 2005.)(1) Practice C 670 and Test Method D 1461 were removedfrom section 2.(2) Practice D 5361 was added to section 7.3.TABLE 1 Precision EstimatesA1s limit d2s limitSingle Operator Precision:12.5-mm nominal max agg. 0.008 0.02319.0-mm nominal max agg. 0.013 0.037Multilaboratory Precision:
44、12.5-mm nominal max agg. 0.015 0.04219.0-mm nominal max agg. 0.015 0.042ABased on an interlaboratory study conducted under NCHRP Project 9-26involving 150-mm diameter specimens with 4.5 % air voids, 26 laboratories, twomaterials (a 12.5-mm mixture and a 19.0-mm mixture), and three replicates.The pre
45、cision statement in 12.1 was derived from data resulting from laborato-ries that compacted samples sent out by the AMRL.D 2726 05a3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard
46、are expressly advised that determination 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 no
47、t revised, either reapproved or 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
48、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 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).D 2726 05a4
