1、Designation: C1252 17Standard Test Methods forUncompacted Void Content of Fine Aggregate (asInfluenced by Particle Shape, Surface Texture, andGrading)1This standard is issued under the fixed designation C1252; the number immediately following the designation indicates the year oforiginal adoption or
2、, 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 These test methods cover the determination of the loose,uncompacted void conten
3、t of a sample of fine aggregate. Whenmeasured on any aggregate of a known grading, void contentprovides an indication of that aggregates angularity,sphericity, and surface texture compared with other fine aggre-gates tested in the same grading. When void content ismeasured on an as-received fine-agg
4、regate grading, it can be anindicator of the effect of the fine aggregate on the workabilityof a mixture in which it may be used.1.2 Three procedures are included for the measurement ofvoid content. Two use graded fine aggregate (standard gradingor as-received grading), and the other uses several in
5、dividualsize fractions for void content determinations:1.2.1 Standard Graded Sample (Test Method A)This testmethod uses a standard fine aggregate grading that is obtainedby combining individual sieve fractions from a typical fineaggregate sieve analysis. See the Section 9 for the grading.1.2.2 Indiv
6、idual Size Fractions (Test Method B)This testmethod uses each of three fine aggregate size fractions: (a)2.36 mm (No. 8) to 1.18 mm (No. 16); (b) 1.18 mm (No. 16)to 600 m (No. 30); and (c) 600 m (No. 30) to 300 m (No.50). For this test method, each size is tested separately.1.2.3 As-Received Grading
7、 (Test Method C)This testmethod uses that portion of the fine aggregate finer than a4.75-mm (No. 4) sieve.1.2.4 See the section on Significance and Use for guidanceon the method to be used.1.3 The values stated in SI units shall be regarded as thestandard.1.4 This standard does not purport to addres
8、s 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.1.5 This international standard was developed in accor-danc
9、e with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Stan
10、dards:2B88 Specification for Seamless Copper Water TubeB88M Specification for Seamless Copper Water Tube (Met-ric)C29/C29M Test Method for Bulk Density (“Unit Weight”)and Voids in AggregateC117 Test Method for Materials Finer than 75-m (No. 200)Sieve in Mineral Aggregates by WashingC125 Terminology
11、Relating to Concrete and Concrete Ag-gregatesC128 Test Method for Relative Density (Specific Gravity)and Absorption of Fine AggregateC136 Test Method for Sieve Analysis of Fine and CoarseAggregatesC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC70
12、2 Practice for Reducing Samples ofAggregate to TestingSizeC778 Specification for Standard SandD75 Practice for Sampling Aggregates2.2 ACI Document:ACI 116R Cement and Concrete Terminology33. Terminology3.1 Terms used in these test methods are defined in Termi-nology C125 or ACI 116R.1These test meth
13、ods are under the jurisdiction of ASTM Committee D04 onRoad and Paving Materials and are the direct responsibility of SubcommitteeD04.51 on Aggregate Tests.Current edition approved May 1, 2017. Published May 2017. Originallyapproved in 1993. Last previous edition approved in 2006 as C1252 06 which w
14、aswithdrawn January 2015 and reinstated May 2017. DOI: 10.1520/C1252-17.2For 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 AS
15、TM website.3Available from American Concrete Institute (ACI), P.O. Box 9094, FarmingtonHills, MI 48333-9094, http:/www.aci-int.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance
16、with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.14. Summary of Test Method4.1 A nominal
17、 100-mL calibrated cylindrical measure isfilled with fine aggregate of prescribed grading by allowing thesample to flow through a funnel from a fixed height into themeasure. The fine aggregate is struck off and its mass isdetermined by weighing. Uncompacted void content is calcu-lated as the differe
18、nce between the volume of the cylindricalmeasure and the absolute volume of the fine aggregate col-lected in the measure. Uncompacted void content is calculatedusing the dry relative density (specific gravity) of the fineaggregate. Two runs are made on each sample and the resultsare averaged.4.1.1 F
19、or a graded sample (Test Method A or Test MethodC), the percent void content is determined directly and theaverage value from two runs is reported.4.1.2 For the individual size fractions (Test Method B), themean percent void content is calculated using the results fromtests of each of the three indi
20、vidual size fractions.5. Significance and Use5.1 Test Methods A and B provide percent void contentdetermined under standardized conditions which depend on theparticle shape and texture of a fine aggregate. An increase invoid content by these procedures indicates greater angularity,less sphericity, r
21、ougher surface texture, or combinationsthereof. A decrease in void content results is associated withmore rounded, spherical, or smooth-surfaced fine aggregate, ora combination thereof.5.2 Test Method C measures the uncompacted void contentof the minus 4.75-mm (No. 4) portion of the as-receivedmater
22、ial. This void content depends on grading as well asparticle shape and texture.5.3 The void content determined on the standard gradedsample (Test Method A) is not directly comparable with theaverage void content of the three individual size fractions fromthe same sample tested separately (Test Metho
23、d B). A sampleconsisting of single-size particles will have a higher voidcontent than a graded sample. Therefore, use either one methodor the other as a comparative measure of shape and texture, andidentify which test method has been used to obtain the reporteddata. Test Method C does not provide an
24、 indication of shapeand texture directly if the grading from sample to samplechanges.5.3.1 The standard graded sample (Test Method A) is mostuseful as a quick test which indicates the particle shapeproperties of a graded fine aggregate. Typically, the materialused to make up the standard graded samp
25、le can be obtainedfrom the remaining size fractions after performing a singlesieve analysis of the fine aggregate.5.3.2 Obtaining and testing individual size fractions (TestMethod B) are more time consuming and require a larger initialsample than using the graded sample. However, Test Method Bprovid
26、es additional information concerning the shape andtexture characteristics of individual sizes.5.3.3 Testing samples in the as-received grading (TestMethod C) may be useful in selecting proportions of compo-nents used in a variety of mixtures. In general, high voidcontent suggests that the material c
27、ould be improved byproviding additional fines in the fine aggregate or morecementitious material may be needed to fill voids betweenparticles.5.3.4 The dry relative denstiy (specific gravity) of the fineaggregate is used in calculating the void content. The effec-tiveness of these test methods of de
28、termining void content andits relationship to particle shape and texture depends on therelative density (specific gravity) of the various size fractionsbeing equal, or nearly so. The void content is actually afunction of the volume of each size fraction. If the type of rockor minerals, or its porosi
29、ty, in any of the size fractions variesmarkedly it may be necessary to determine the specific gravityof the size fractions used in the test.5.4 Void content information from Test Methods A, B, or Cwill be useful as an indicator of properties such as: the mixingwater demand of hydraulic cement concre
30、te; flowability,pumpability, or workability factors when formulating grouts ormortars; or, in bituminous concrete, the effect of the fineaggregate on stability and voids in the mineral aggregate; or thestability of the fine-aggregate portion of a base course aggre-gate.6. Apparatus6.1 Cylindrical Me
31、asureAright cylinder of approximately100-mL capacity having an inside diameter of approximately39 mm and an inside height of approximately 86 mm made ofdrawn copper water tube meeting the requirements of Specifi-cation B88,TypeMorB88M, Type C. The bottom of themeasure shall be metal at least 6 mm th
32、ick, shall be firmlysealed to the tubing, and shall be provided with means foraligning the axis of the cylinder with that of the funnel. SeeFig. 1.6.2 FunnelThe lateral surface of the right frustum of acone sloped 60 6 4 from the horizontal with an opening of12.7 6 0.6-mm diameter. The funnel sectio
33、n shall be a piece ofmetal, smooth on the inside and at least 38 mm high. It shallhave a volume of at least 200 mL or shall be provided with asupplemental glass or metal container to provide the requiredvolume. See Fig. 2.NOTE 1Pycnometer top C94554is satisfactory for the funnel section,except that
34、the size of the opening has to be enlarged and any burrs or lipsthat are apparent should be removed by light filing or sanding before use.This pycnometer top must be used with a suitable glass jar with the bottomremoved (Fig. 2).6.3 Funnel StandA three- or four-legged support capableof holding the f
35、unnel firmly in position with the axis of thefunnel colinear (within a 4 angle and a displacement of 2 mm)with the axis of the cylindrical measure. The funnel openingshall be 115 6 2 mm above the top of the cylinder. A suitablearrangement is shown in Fig. 2.4The sole source of supply of the apparatu
36、s known to the committee at this timeis Hogentogler and Co., Inc., 9515 Gerwig, Columbia, MD 21045. If you are awareof alternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical c
37、ommittee,1which you may attend.C1252 172FIG. 1 Nominal 100-mL Cylindrical MeasureFIG. 2 Suitable Funnel Stand Apparatus with Cylindrical Measurein PlaceC1252 1736.4 Glass PlateA square glass plate approximately 60 by60 mm with a minimum 4-mm thickness used to calibrate thecylindrical measure.6.5 Pan
38、A metal or plastic pan of sufficient size to containthe funnel stand and to prevent loss of material. The purpose ofthe pan is to catch and retain fine aggregate particles thatoverflow the measure during filling and strike-off.6.6 Metal Spatula, with a blade approximately 100 mmlong, and at least 20
39、 mm wide, with straight edges. The endshall be cut at a right angle to the edges. The straight edge ofthe spatula blade is used to strike off the fine aggregate.6.7 Scale or Balance, accurate and readable to 60.1 gwithin the range of use, capable of weighing the cylindricalmeasure and its contents.7
40、. Sampling7.1 Obtain the sample(s) used for this test in accordancewith Practices D75 and C702, or from sieve analysis samplesused for Test Method C136, or from aggregate extracted froma bituminous concrete specimen. For Methods A and B, washthe sample over a 150-m (No. 100) or 75-m (No. 200) sievei
41、n accordance with Test Method C117 and then dry and sieveinto separate size fractions in accordance with the proceduresof Test Method C136. Maintain the necessary size fractionsobtained from one (or more) sieve analysis in a dry conditionin separate containers for each size. For Method C, dry a spli
42、tof the as-received sample in accordance with the dryingprocedure in Test Method C136.8. Calibration of Cylindrical Measure8.1 Apply a light coat of grease to the top edge of the dry,empty cylindrical measure. Weigh the measure, grease, andglass plate. Fill the measure with freshly boiled, deionized
43、water at a temperature of 18 to 24 C. Record the temperatureof the water. Place the glass plate on the measure, being surethat no air bubbles remain. Dry the outer surfaces of themeasure and determine the combined mass of measure, glassplate, grease, and water by weighing. Following the finalweighin
44、g, remove the grease and determine the mass of theclean, dry, empty measure for subsequent tests.8.2 Calculate the volume of the measure as follows:V 51000MDwhere:V = volume of cylinder, mL,M = net mass of water, g, andD = density of water, kg/m3(see table in Test MethodC29/C29M for density at the t
45、emperature used.)Determine the volume to the nearest 0.1 mL.NOTE 2If the volume of the measure is greater than 100.0 mL, it maybe desirable to grind the upper edge of the cylinder until the volume isexactly 100.0 mL to simplify subsequent calculations.9. Preparation of Test Samples9.1 Test Method AS
46、tandard Graded SampleWeigh outand combine the following quantities of fine aggregate whichhave been dried and sieved in accordance with Test MethodC136.Individual Size Fraction Mass, g2.36 mm (No. 8) to 1.18 mm (No. 16) 441.18 mm (No. 16) to 600 m (No. 30) 57600 m (No. 30) to 300 m (No. 50) 72300 m
47、(No. 50) to 150 m (No. 100) 17190The tolerance on each of these amounts is 60.2 g.9.2 Test Method BIndividual Size FractionsPrepare aseparate 190-g sample of fine aggregate, dried and sieved inaccordance with Test Method C136, for each of the followingsize fractions:Individual Size Fraction Mass, g2
48、.36 mm (No. 8) to 1.18 mm (No. 16) 1901.18 mm (No. 16) to 600 m (No. 30) 190600 m (No. 30) to 300 m (No. 50) 190The tolerance on each of these amounts is 61 g. Do not mixthese samples together. Each size is tested separately.9.3 Test Method C As-Received GradingPass the sample(dried in accordance wi
49、th Test Method C136) through a4.75-mm (No. 4) sieve. Obtain a 190 6 1-g sample of thematerial passing the 4.75-mm (No. 4) sieve for test.9.4 Relative Density (Specific Gravity) of FineAggregateIf the dry relative density (specific gravity) of fineaggregate from the source is unknown, determine it on theminus 4.75-mm (No. 4) material in accordance with TestMethod C128. Use this value in subsequent calculations unlesssome size fractions differ by more than 0.05 from the relativedensity (specific gravity) typical of the complete sample, inwhich ca
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