ASTM_C_128-15.pdf

Designation:C128-15INTERNATIONALStandard Test Method forRelative Density(Specific Gravity)and Absorption of FineAggregateThis standard is issued under the fixed designation C128: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 indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.ScopeSieve in Mineral Aggregates by Washing1.I This test method covers the determination of relativeC125 Terminology Relating to Concrete and Concrete Ag-density(specific gravity)and the absorption of fine aggregates.gregatesThe relative density(specific gravity),a dimensionless quality,C127 Test Method for Relative Density(Specific Gravity)is expressed as oven-dry(OD),saturated-surface-dry(SSD),orand Absorption of Coarse Aggregateas apparent relative density(specific gravity).The OD relativeC330 Specification for Lightweight Aggregates for Struc-density is determined after drying the aggregate.The SSDtural Concreterelative density and absorption are determined after soaking theC332 Specification for Lightweight Aggregates for Insulat-aggregate in water for a prescribed duration.ing ConcreteC188 Test Method for Density of Hydraulic Cement1.2 This test method is not intended to be used for light-C566 Test Method for Total Evaporable Moisture Content ofweight aggregates that comply with Specification C332 GroupAggregate by DryingI aggregates.C670 Practice for Preparing Precision and Bias Statements1.3 The values stated in SI units are to be regarded asfor Test Methods for Construction Materialsstandard.No other units of measurement are included in thisC702 Practice for Reducing Samples of Aggregate to Testingstandard.Size1.4 The text of this test method references notes andC1252 Test Methods for Uncompacted Void Content of Finefootnotes that provide explanatory material.These notes andAggregate(as Influenced by Particle Shape,Surfacefootnotes(excluding those in tables and figures)shall not beTexture,and Grading)(Withdrawn 2015)3considered as requirements of this test method.D75 Practice for Sampling AggregatesD854 Test Methods for Specific Gravity of Soil Solids by1.5 This standard does not purport to address all of theWater Pycnometersafery concerns,if any,associated with its use.It is the2.2 AASHTO Standard:responsibility of the user of this standard to establish appro-AASHTO T 84 Specific Gravity and Absorption of Finepriate safery and health practices and determine the applica-bility of regulatory limitations prior to use.Aggregates3.Terminology2.Referenced Documents3.1 Definitions-For definitions of terms used in this2.1 ASTM Standards:2standard,refer to Terminology C125.C29/C29M Test Method for Bulk Density(Unit Weight)and Voids in Aggregate4.Summary of Test MethodC70 Test Method for Surface Moisture in Fine Aggregate4.1 A sample of aggregate is immersed in water for 244C117 Test Method for Materials Finer than 75-um(No.200)h to essentially fill the pores.It is then removed from the water,the water is dried from the surface of the particles,and themass determined.Subsequently,the sample(or a portion of it)This test method is under the jurisdiction of ASTM Committee C09 onis placed in a graduated container and the volume of the sampleConcrete and Concrete Aggregatesand is the direct responsibility of SubcommitteeC09.20 on Normal Weight Aggregates.is determined by the gravimetric or volumetric method.Finally.Current edition approved Jan.I.2015.Published March 2015.Originallyapproved in 1936.Last previous edition approved in 2012 as C128-12.DOl:10.1520C0128-15.The last approved version of this historical standard is referenced on2 For referenced ASTM standards,visit the ASTM website,www.astm.org.orwww.astm.org.contact ASTM Customer Service at serviceastm.org.For Annual Book of ASTM4 Available from American Association of State Highway and TransportationStandards volume information nefer to the standands Document Summary pnoe.onOfficials(AASHTO)444 N Canitol St NW Suite 249 Washineton DC 20001C128-15the sample is oven-dried and the mass determined again.Usingby the prescribed 24-h soak,as will the relative densitythe mass values thus obtained and formulas in this test method.(specific gravity)(SSD).it is possible to calculate relative density(specific gravity)andabsorption.6.Apparatus6.1 Balance-A balance or scale having a capacity of I kg5.Significance and Useor more,sensitive to 0.I g or less,and accurate within 0.1 of5.1 Relative density(specific gravity)is the ratio of mass ofthe test load at any point within the range of use for this testan aggregate to the mass of a volume of water equal to themethod.Within any 100-g range of test load,a differencevolume of the aggregate particles-also referred to as thebetween readings shall be accurate within 0.1 g.absolute volume of the aggregate.It is also expressed as the6.2 Pycnometer(for Use with Gravimetric Procedure-Aratio of the density of the aggregate particles to the density offlask or other suitable container into which the fine aggregatewater.Distinction is made between the density of aggregatetest sample can be readily introduced and in which the volumeparticles and the bulk density of aggregates as determined bycontent can be reproduced within 0.I cm.The volume ofTest Method C29/C29M.which includes the volume of voidsthe container filled to mark shall be at least 50 greater thanbetween the particles of aggregates.the space required to accommodate the test sample.A volu-5.2 Relative density is used to calculate the volume occu-metric flask of 500-cmcapacity or a fruit jar fitted with apied by the aggregate in various mixtures containing aggregatepycnometer top is satisfactory for a 500-g test sample of mostincluding hydraulic cement concrete,bituminous concrete,andfne aggregates.other mixtures that are proportioned or analyzed on an absolute6.3 Flask(for Use with Volumetric Procedure)-A Le Chat-volume basis.Relative density(specific gravity)is also used inelier flask as described in Test Method C188 is satisfactory forthe computation of voids in aggregate in Test Method C29/an approximately 55-g test sample.C29M and in Test Method C1252.Relative density(specific6.4 Mold and Tamper for Surface Moisture Test-The metalgravity)(SSD)is used in the determination of surface moisturemold shall be in the form of a frustum of a cone withon fine aggregate by displacement of water in Test Methoddimensions as follows:40+3-mm inside diameter at the top,C70.Relative density(specific gravity)(SSD)is used if the90 3-mm inside diameter at the bottom,and 75 3 mm inaggregate is in a saturated surface-dry condition,that is,if itsheight,with the metal having a minimum thickness of 0.8 mm.absorption has been satisfied.Alternatively,the relative densityThe metal tamper shall have a mass of 340 15 g and a flat(specific gravity)(OD)is used for computations when thecircular tamping face 25 3 mm in diameter.aggregate is dry or assumed to be dry.6.5 Oven-An oven of sufficient size,capable of maintain-5.3 Apparent relative density(specific gravity)pertain to theing a uniform temperature of 110 5 C(230 9 F).solid material making up the constituent particles not includingthe pore space within the particles that is accessible to water.7.SamplingThis value is not widely used in construction aggregate7.1 Sample the aggregate in accordance with Practice D75.technologyThoroughly mix the sample and reduce it to obtain a test5.4 Absorption values are used to calculate the change in thespecimen of approximately I kg using the applicable proce-mass of an aggregate material due to water absorbed in the poredures described in Practice C702.spaces within the constituent particles,compared to the drycondition,if it is deemed that the aggregate has been in contact8.Preparation of Test Specimenwith water long enough to satisfy most of the absorption8.I Place the test specimen in a suitable pan or vessel andpotential.The laboratory standard for absorption is that ob-dry in the oven to constant mass at a temperature of 1105tained after submerging dry aggregate for a prescribed periodC(230+9 F).Allow it to cool to comfortable handlingof time.Aggregates mined from below the water table com-temperature(approximately 50C).cover with water,either bymonly have a moisture content greater than the absorptionimmersion or by the addition of at least 6%moisture to thedetermined by this test method,if used without opportunity tofine aggregate,and permit to stand for 24+4 h.Whendry prior to use.Conversely,some aggregates that have notSpecification C330 or Specification C332 Group II lightweightbeen continuously maintained in a moist condition until usedaggregates are used,immerse the aggregate in water at roomare likely to contain an amount of absorbed moisture less thantemperature for a period of 724 h,stirring for at least onethe 24-h soaked condition.For an aggregate that has been inminute every 24 h.contact with water and that has free moisture on the particle8.1.1 When the absorption and relative density(specificsurfaces,the percentage of free moisture is determined bygravity)values are to be used in proportioning concretededucting the absorption from the total moisture contentmixtures in which the aggregates will be in their naturallydetermined by Test Method C566 by drying.moist condition,the requirement in 8.I for initial drying is5.5 The general procedures described in this test method areoptional,and,if the surfaces of the particles in the sample havesuitable for determining the absorption of aggregates that havebeen kept continuously wet until tested,the requirement in 8.Ihad conditioning other than the 24-h soak,such as boilingfor244 h soaking or724 h is also optional.water or vacuum saturation.The values obtained for absorptionNor 1-Values for absorption and for relative density(specificby other test methods will be different than the values obtainedgravity)(SSD)may be significantly higher for aggregate not oven driedC128-15before soaking than for the same aggregate treated in accordance with 8.1.at the onset of the surface-dry condition.with the hand lightly8.2 Decant excess water with care to avoid loss of fines(seepat approximately 100 g of the material on a flat,dry,clean,also Appendix X1).spread the sample on a flat nonabsorbentdark or dull nonabsorbent surface such as a sheet of rubber.asurface exposed to a gently moving current of warm air,andworn oxidized,galvanized,or steel surface,or a black-paintedstir frequently to secure homogeneous drying.Employ me-metal surface.After I to 3 s,remove the fine aggregate.Ifchanical aids such as tumbling or stirring to assist in achievingnoticeable moisture shows on the test surface for more than Ithe saturated surface-dry condition,if desired.Continue thisto 2 s then surface moisture is considered to be present on theoperation until the test specimen approaches a free-flowingfine aggregatecondition.Follow the procedure in 8.3 to determine if surface(3)Colorimetric procedures described by Kandhal and Lee,moisture is still present on the constituent fine aggregateHighway Research Record No.307,p.44.particles.Make the first trial for surface moisture when there is(4)For reaching the saturated surface-dry condition on astill some surface water in the test specimen.Continue dryingsingle size material that slumps when wet,hard-finish paperwith constant stirring and test at frequent intervals until the testtowels can be used to surface dry the material until the point isindicates that the specimen has reached a surface-dry condi-just reached where the paper towel does not appear to betion.If the first trial of the surface moisture test indicates thatpicking up moisture from the surfaces of the fine aggregatemoisture is not present on the surface,it has been dried past theparticles.saturated surface-dry condition.In this case,thoroughly mix afew millilitres of water with the fine aggregate and permit the9.Procedurespecimen to stand in a covered container for 30 min.Then9.1 Test by either the gravimetric procedure in 9.2 or theresume the process of drying and testing at frequent intervalsvolumetric procedure in 9.3.Make all determinations of massfor the onset of the surface-dry condition.to 0.1 g.8.3 Test for Surface Moisture-Hold the mold firmly on a9.2 Gravimetric(Pycnometer)Procedure:smooth nonabsorbent surface with the large diameter down.9.2.1 Partially fill the pycnometer with water.Introduce intoPlace a portion of the partially dried fine aggregate loosely inthe pycnometer 500 10 g of saturated surface-dry finethe mold by filling it to overflowing and heaping additionalaggregate prepared as described in Section 8.and fill withmaterial above the top of the mold by holding it with theadditional water to approximately 90 of capacity.Agitate thecupped fingers of the hand holding the mold.Lightly tamp thepycnometer as described in 9.2.1.1(manually)or 9.2.1.2fine aggregate into the mold with 25 light drops of the tamper.(mechanically).Start each drop approximately 5 mm above the top surface of9.2.1.1 Manually roll,invert,or agitate the pycnometer(orthe fine aggregate.Permit the tamper to fall freely underuse a combination of these actions)to eliminate visible airgravitational attraction on each drop.Adjust the starting heightbubbles.to the new surface elevation after each drop and distribute theNorE 3-About 15 to 20 min are normally required to eliminate the airdrops over the surface.Remove loose sand from the base andbubbles by manual methods.Dipping the tip of a paper towel into thelift the mold vertically.If surface moisture is still present,thepycnometer has been found to be useful in dispersing the foam thatfine aggregate will retain the molded shape.Slight slumping ofsometimes builds up when eliminating the air bubbles.Optionally,a smallthe molded fine aggregate indicates that it has reached aamount of isopropyl alcohol may be used to disperse the foam.surface-dry condition.9.2.1.2 Mechanically agitate the pycnometer by external8.3.1 Some fine aggregate with predominately angular-vibration in a manner that will not degrade the sample.A levelshaped particles or with a high proportion of fines does notof agitation adjusted to just set individual particles in motion isslump in the cone test upon reaching the surface-dry condition.sufficient to promote de-airing without degradation.A me-Test by dropping a handful of the fine aggregate from the conechanical agitator shall be considered acceptable for use iftest onto a surface from a height of 100 to 150 mm.andcomparison tests for each six-month period of use showobserve for fines becoming airborne:presence of airborne finesvariations less that the acceptable range of two results(d2s)indicates this problem.For these materials,consider theindicated in Table I from the results of manual agitation on thesaturated surface-dry condition as the point that one side of thesame material.fine aggregate slumps slightly upon removing the mold.9.2.2 After eliminating all air bubbles,adjust the tempera-ture of the pycnometer and its contents to 23.0+2.0 C ifNor 2-The following criteria have also been used on materials thatdo not readily slump:necessary by partial immersion in circulating water,and bring(/Provisional Cone Test-Fill the cone mold as describedthe water level in the pycnometer to its calibrated capacity.in 8.3 except only use 10 drops of the tamper.Add more fineDetermine the total mass of the pycnometer.specimen.andaggregate and use 10 drops of the tamper again.Then addwater.material two more times using 3 and 2 drops of the tamper,9.2.3 Remove the fine aggregate from the pycnometer,dryrespectively.Level off the material even with the top of thein the oven to constant mass at a temperature of 1105 Cmold,remove loose material from the base:and lift the mold(2309F).cool in air at room temperature for I2 h,andvertically.determine the mass.(2)Provisional Surface Test-If airborne fines are noted9.2.4 Determine the mass of the pycnometer filled to itswhen the fine aggregate is such that it will not slump when itcalibrated capacity with water at 23.02.0 C.is at a moisture condition,add more moisture to the sand,and9.3 Volumetric(Le Chatelier Flask)Procedure:4c128-154 h,and AASHTO Test Method T 84 requires a saturation13.Keywordsperiod of 15 to 19 h.This difference has been found to have aninsignificant effect on the precision indices.The data are based13.1 absorption:aggregate;apparent relative density:fineaggregate;relative density:specific gravityon the analyses of more than 100 paired test results from 40 to100 laboratories.12.2 Bias-Since there is no accepted reference materialsuitable for determining the bias for this test method,nostatement on bias is being made.APPENDIXES(Nonmandatory Information)X1.POTENTIAL DIFFERENCES IN BULK RELATIVE DENSITY AND ABSORPTION DUE TO PRESENCE OF MATERIALFINER THAN 75 pmX1.I It has been found that there may be significantdepends on both the amount of the material finer than 75 umdifferences in bulk relative density and absorption between finepresent and the nature of the material.When the material fineraggregate samples tested with the material finer than 75 umthan 75 um is less than about 4 by mass,the difference in(No.200)present and not present in the samples.Samples fromrelative density between washed and unwashed samples is lesswhich the material finer than 75 um is not removed usuallythan 0.03.When the material finer than 75 um is greater thangive a higher absorption and a lower bulk relative densityabout 8%by mass,the difference in relative density obtainedcompared with testing the same fine aggregate from which thebetween washed and unwashed samples may be as great asmaterial finer than 75 um is removed following the procedures0.13.It has been found that the relative density determined onof Test Method C117.Samples with material finer than 75 umfine aggregate from which the material finer than 75 um hasmay build up a coating around the coarser fine aggregatebeen removed prior to testing more accurately reflects theparticles during the surface drying process.The resultantrelative density of the material.relative density and absorption that is subsequently measured isX1.2 The material finer than 75 um,which is removed,canthat of the agglomerated and coated particles and not that of thebe assumed to have the same relative density as the fineparent material.The difference in absorption and relativeaggregate.Alternatively,the relative density(specific gravity)density determined between samples from which the materialof the material finer than 75 um may be further evaluated usingfiner than 75 um have not been removed and samples fromTest Method D854,however,this test determines the apparentwhich the material finer than 75 um have been removedrelative density and not the bulk relative density.X2.INTERRELATIONSHIPS BETWEEN RELATIVE DENSITIES(SPECIFIC GRAVITIES)AND ABSORPTION AS DEFINEDIN TEST METHODS C127 AND C128X2.1 This appendix gives mathematical interrelationshipsamong the three types of relative densities(specific gravities)5,=1AAS(X2.2)and absorption.These may be useful in checking the consis-5-1001-10tency of reported data or calculating a value that was not1reported by using other reported data.orS.=1+A/100A(X2.3)X2.2 Where:00S=relative density(specific gravity)(OD).5S.relative density(specific gravity)(SSD)S=apparent relative density(apparent specific gravity).1=00S,-andA absorption,in%A-(昏-(X2.4)Calculate the values of each as follows:S,=(1+A/100)S(X2.1)(X2.5)