1、Designation: C127 12Standard Test Method forDensity, Relative Density (Specific Gravity), and Absorptionof Coarse Aggregate1This standard is issued under the fixed designation C127; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method covers th
3、e determination of the averagedensity of a quantity of coarse aggregate particles (not includ-ing the volume of voids between the particles), the relativedensity (specific gravity), and the absorption of the coarseaggregate. Depending on the procedure used, the density(kg/m3(lb/ft3) is expressed as
4、oven-dry (OD), saturated-surface-dry (SSD), or as apparent density. Likewise, relativedensity (specific gravity), a dimensionless quantity, is ex-pressed as OD, SSD, or as apparent relative density (apparentspecific gravity). The OD density and OD relative density aredetermined after drying the aggr
5、egate. The SSD density, SSDrelative density, and absorption are determined after soakingthe aggregate in water for a prescribed duration.1.2 This test method is used to determine the density of theessentially solid portion of a large number of aggregateparticles and provides an average value represe
6、nting thesample. Distinction is made between the density of aggregateparticles as determined by this test method, and the bulkdensity of aggregates as determined by Test Method C29/C29M, which includes the volume of voids between theparticles of aggregates.1.3 This test method is not intended to be
7、used withlightweight aggregates that comply with Specification C332Group I aggregates.1.4 The values stated in SI units are to be regarded as thestandard for conducting the tests. The test results for densityshall be reported in either SI units or inch-pound units, asappropriate for the use to be ma
8、de of the results.1.5 The text of this test method references notes andfootnotes which provide explanatory material. These notes andfootnotes (excluding those in tables and figures) shall not beconsidered as requirements of this test method.1.6 This standard does not purport to address all of thesaf
9、ety 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:2C29/C29M Test Method for Bulk D
10、ensity (“Unit Weight”)and Voids in AggregateC125 Terminology Relating to Concrete and Concrete Ag-gregatesC128 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Fine AggregateC136 Test Method for Sieve Analysis of Fine and CoarseAggregatesC330 Specification for Lightweig
11、ht Aggregates for Struc-tural ConcreteC332 Specification for Lightweight Aggregates for Insulat-ing ConcreteC566 Test Method for Total Evaporable Moisture Contentof Aggregate by DryingC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC702 Practice fo
12、r Reducing Samples of Aggregate to Test-ing SizeD75 Practice for Sampling AggregatesD448 Classification for Sizes of Aggregate for Road andBridge ConstructionE11 Specification for Woven Wire Test Sieve Cloth and TestSieves2.2 AASHTO Standard:AASHTO No. T 85 Specific Gravity and Absorption ofCoarse A
13、ggregate33. Terminology3.1 Definitions:1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.20 on Normal Weight Aggregates.Current edition approved April 1, 2012. Published May 2012. Originallyapprove
14、d in 1936. Last previous edition approved in 2007 as C12707. DOI:10.1520/C0127-12.2For 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 pag
15、e onthe ASTM website.3Available from American Association of State Highway and TransportationOfficials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001,http:/www.transportation.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, U
16、nited States.3.1.1 absorption, nthe increase in mass of aggregate dueto water penetration into the pores of the particles during aprescribed period of time, but not including water adhering tothe outside surface of the particles, expressed as a percentageof the dry mass.3.1.2 oven-dry (OD), adjrelat
17、ed to aggregate particles,the condition in which the aggregates have been dried byheating in an oven at 110 6 5 C for sufficient time to reach aconstant mass.3.1.3 saturated-surface-dry (SSD), adjrelated to aggre-gate particles, the condition in which the permeable pores ofaggregate particle are fil
18、led with water to the extent achievedby submerging in water for the prescribed period of time, butwithout free water on the surface of the particles.3.1.4 density, nthe mass per unit volume of a material,expressed as kilograms per cubic metre (pounds per cubicfoot).3.1.4.1 density (OD), nthe mass of
19、 oven dry aggregate perunit volume of aggregate particles, including the volume ofpermeable and impermeable pores within the particles, but notincluding the voids between the particles.3.1.4.2 density (SSD), nthe mass of saturated-surface-dryaggregate per unit volume of the aggregate particles, incl
20、udingthe volume of impermeable pores and permeable, water-filledpores within the particles, but not including the voids betweenthe particles.3.1.4.3 apparent density, nthe mass per unit volume of theimpermeable portion of the aggregate particles.3.1.5 relative density (specific gravity), nthe ratio
21、of thedensity of a material to the density of distilled water at a statedtemperature; the values are dimensionless.3.1.5.1 relative density (specific gravity) (OD), nthe ratioof the density (OD) of the aggregate to the density of distilledwater at a stated temperature.3.1.5.2 relative density (speci
22、fic gravity) (SSD), nthe ratioof the density (SSD) of the aggregate to the density of distilledwater at a stated temperature.3.1.5.3 apparent relative density (apparent specific gravity),nthe ratio of the apparent density of aggregate to the densityof distilled water at a stated temperature.3.1.6 Fo
23、r definitions of other terms related to aggregates,see Terminology C125.4. Summary of Test Method4.1 A sample of aggregate is immersed in water for 24 6 4h to essentially fill the pores. It is then removed from the water,the water dried from the surface of the particles, and the massdetermined. Subs
24、equently, the volume of the sample is deter-mined by the displacement of water method. Finally, thesample is oven-dried and the mass determined. Using the massvalues thus obtained and formulas in this test method, it ispossible to calculate density, relative density (specific gravity),and absorption
25、.5. Significance and Use5.1 Relative density (specific gravity) is the characteristicgenerally used for calculation of the volume occupied by theaggregate in various mixtures containing aggregate, includingportland cement concrete, bituminous concrete, and othermixtures that are proportioned or anal
26、yzed on an absolutevolume basis. Relative density (specific gravity) is also used inthe computation of voids in aggregate in Test Method C29/C29M. Relative density (specific gravity) (SSD) is used if theaggregate is wet, that is, if its absorption has been satisfied.Conversely, the relative density
27、(specific gravity) (OD) is usedfor computations when the aggregate is dry or assumed to bedry.5.2 Apparent density and apparent relative density (apparentspecific gravity) pertain to the solid material making up theconstituent particles not including the pore space within theparticles which is acces
28、sible to water.5.3 Absorption values are used to calculate the change in themass of an aggregate due to water absorbed in the pore spaceswithin the constituent particles, compared to the dry condition,when it is deemed that the aggregate has been in contact withwater long enough to satisfy most of t
29、he absorption potential.The laboratory standard for absorption is that obtained aftersubmerging dry aggregate for a prescribed period of time.Aggregates mined from below the water table commonly havea moisture content greater than the absorption determined bythis test method, if used without opportu
30、nity to dry prior to use.Conversely, some aggregates which have not been continu-ously maintained in a moist condition until used are likely tocontain an amount of absorbed moisture less than the 24-hsoaked condition. For an aggregate that has been in contactwith water and that has free moisture on
31、the particle surfaces,the percentage of free moisture is determined by deducting theabsorption from the total moisture content determined by TestMethod C566.5.4 The general procedures described in this test method aresuitable for determining the absorption of aggregates that havehad conditioning oth
32、er than the 24-h soak, such as boilingwater or vacuum saturation. The values obtained for absorptionby other test methods will be different than the values obtainedby the prescribed soaking, as will the relative density (specificgravity) (SSD).6. Apparatus6.1 BalanceA device for determining mass tha
33、t is sensi-tive, readable, and accurate to 0.05 % of the sample mass atany point within the range used for this test, or 0.5 g,whichever is greater. The balance shall be equipped withsuitable apparatus for suspending the sample container in waterfrom the center of the platform or pan of the balance.
34、6.2 Sample ContainerA wire basket of 3.35 mm (No. 6)or finer mesh, or a bucket of approximately equal breadth andheight, with a capacity of 4 to 7 L for 37.5-mm (112-in.)nominal maximum size aggregate or smaller, and a largercontainer as needed for testing larger maximum size aggregate.The container
35、 shall be constructed so as to prevent trapping airwhen the container is submerged.6.3 Water TankA watertight tank into which the samplecontainer is placed while suspended below the balance.6.4 SievesA 4.75-mm (No. 4) sieve or other sizes asneeded (see 7.2-7.4), conforming to Specification E11.6.5 O
36、venAn oven of sufficient size, capable of maintain-ing a uniform temperature of 110 6 5 C (230 6 9 F).C127 1227. Sampling7.1 Sample the aggregate in accordance with Practice D75.7.2 Thoroughly mix the sample of aggregate and reduce it tothe approximate quantity needed using the applicable proce-dure
37、s in Practice C702. Reject all material passing a 4.75-mm(No. 4) sieve by dry sieving and thoroughly washing to removedust or other coatings from the surface. If the coarse aggregatecontains a substantial quantity of material finer than the4.75-mm sieve (such as for Size No. 8 and 9 aggregates inCla
38、ssification D448), use the 2.36-mm (No. 8) sieve in place ofthe 4.75-mm sieve. Alternatively, separate the material finerthan the 4.75-mm sieve and test the finer material according toTest Method C128.NOTE 1If aggregates smaller than 4.75 mm (No. 4) are used in thesample, check to ensure that the si
39、ze of the openings in the samplecontainer is smaller than the minimum size aggregate.7.3 The minimum mass of test sample to be used is given asfollows. Testing the coarse aggregate in several size fractions ispermitted. If the sample contains more than 15 % retained onthe 37.5-mm (112-in.) sieve, te
40、st the material larger than 37.5mm in one or more size fractions separately from the smallersize fractions. When an aggregate is tested in separate sizefractions, the minimum mass of test sample for each fractionshall be the difference between the masses prescribed for themaximum and minimum sizes o
41、f the fraction.Nominal Maximum Size,mm (in.)Minimum Mass of TestSample, kg (lb)12.5 (12) or less 2 (4.4)19.0 (34) 3 (6.6)25.0 (1) 4 (8.8)37.5 (112)51)50 (2) 8 (18)63 (212) 12 (26)75 (3) 18 (40)90 (312) 25 (55)100 (4) 40 (88)125 (5) 75 (165)7.4 If the sample is tested in two or more size fractions,de
42、termine the grading of the sample in accordance with TestMethod C136, including the sieves used for separating the sizefractions for the determinations in this method. In calculatingthe percentage of material in each size fraction, ignore thequantity of material finer than the 4.75-mm (No. 4) sieve
43、(or2.36-mm (No. 8) sieve when that sieve is used in accordancewith 7.2).NOTE 2When testing coarse aggregate of large nominal maximumsize requiring large test samples, it may be more convenient to perform thetest on two or more subsamples, and the values obtained combined for thecomputations describe
44、d in Section 9.8. Procedure8.1 Dry the test sample in the oven to constant mass at atemperature of 110 6 5 C, cool in air at room temperature for1 to 3 h for test samples of 37.5-mm (112-in.) nominalmaximum size, or longer for larger sizes until the aggregate hascooled to a temperature that is comfo
45、rtable to handle (approxi-mately 50 C). Subsequently immerse the aggregate in water atroom temperature for a period of 24 6 4 h. When SpecificationC330 or Specification C332 Group II lightweight aggregatesare used, immerse the aggregate in water at room temperaturefor a period of 72 6 4 h, stirring
46、for at least one minute every24 h.8.2 When the absorption and relative density (specificgravity) values are to be used in proportioning concretemixtures in which the aggregates will be in their naturallymoist condition, the requirement in 8.1 for initial drying isoptional, and, if the surfaces of th
47、e particles in the sample havebeen kept continuously wet until tested, the requirement in 8.1for 24 6 4hor726 4 h soaking is also optional.NOTE 3Values for absorption and relative density (specific gravity)(SSD) may be significantly higher for aggregate not oven dried beforesoaking than for the same
48、 aggregate treated in accordance with 8.1. Thisis especially true of particles larger than 75 mm since the water may notbe able to penetrate the pores to the center of the particle in the prescribedsoaking period.8.3 Remove the test sample from the water and roll it in alarge absorbent cloth until a
49、ll visible films of water areremoved. Wipe the larger particles individually. A movingstream of air is permitted to assist in the drying operation. Takecare to avoid evaporation of water from aggregate pores duringthe surface-drying operation. Determine the mass of the testsample in the saturated surface-dry condition. Record this andall subsequent masses to the nearest 0.5 g or 0.05 % of thesample mass, whichever is greater.8.4 After determining the mass in air, immediately place thesaturated-surface-dry test sample in the sample container anddeterm
