1、Designation: C331/C331M 10Standard Specification forLightweight Aggregates for Concrete Masonry Units1This standard is issued under the fixed designation C331/C331M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last
2、revision. A number in parentheses indicates the year of last reapproval.A superscript 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. Scope*1.1 This specification covers lightweight agg
3、regates in-tended for use in concrete masonry units when a primeconsideration is to reduce the density of the units.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsyst
4、em shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard. Some values have only SI units because theinch-pound equivalents are not used in practice.NOTE 1Sieve size is identified by its standard designation in Speci-fication E11
5、. The alternative designation given in parentheses is forinformation only and does not represent a different standard sieve size.1.3 The text of this specification references notes andfootnotes which provide explanatory material. These notes andfootnotes (excluding those in tables and figures) shall
6、 not beconsidered as requirements of the standard.2. Referenced Documents2.1 ASTM Standards:2C29/C29M Test Method for Bulk Density (“Unit Weight”)and Voids in AggregateC40 Test Method for Organic Impurities in Fine Aggregatesfor ConcreteC114 Test Methods for Chemical Analysis of HydraulicCementC136
7、Test Method for Sieve Analysis of Fine and CoarseAggregatesC142 Test Method for Clay Lumps and Friable Particles inAggregatesC151 Test Method for Autoclave Expansion of HydraulicCementC157/C157M Test Method for Length Change of HardenedHydraulic-Cement Mortar and ConcreteC641 Test Method for Iron St
8、aining Materials in Light-weight Concrete AggregatesC702 Practice for Reducing Samples of Aggregate to Test-ing SizeC1262 Test Method for Evaluating the Freeze-Thaw Dura-bility of Dry-Cast Segmental Retaining Wall Units andRelated Concrete UnitsD75 Practice for Sampling AggregatesE11 Specification f
9、or Woven Wire Test Sieve Cloth and TestSieves3. Aggregate Types3.1 Three general types of lightweight aggregates are cov-ered by this specification, as follows:3.1.1 Aggregates prepared by expanding, pelletizing, orsintering products such as blast-furnace slag, clay, diatomite,fly ash, shale, or sla
10、te, and3.1.2 Aggregates prepared by processing natural materials,such as pumice, scoria, or tuff, and3.1.3 Aggregates consisting of end products of coal or cokecombustion.3.2 The aggregates shall be composed predominately oflightweight-cellular and granular inorganic material.4. Chemical Composition
11、4.1 Lightweight aggregates shall not contain excessiveamounts of deleterious substances, as determined by thefollowing limits:4.1.1 Organic Impurities (Test Method C40)Lightweightaggregates subjected to the test for organic impurities thatproduce a color darker than the standard shall be rejected,un
12、less it is demonstrated that the discoloration is due to smallquantities of materials not harmful to the concrete.1This specification is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.21 on Lightweight Aggregates an
13、d Concrete.Current edition approved Dec. 15, 2010. Published January 2011. Originallyapproved in 1953. Last previous edition approved in 2005 as C33105. DOI:10.1520/C0331_C0331M-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.or
14、g. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States
15、.4.1.2 Staining (Test Method C641)An aggregate produc-ing a stain index of 60 or higher shall be rejected when thedeposited stain is found upon chemical analysis to contain aniron content, expressed as Fe2O3equal to or greater than 1.5mg/200 g of sample.4.1.3 Loss on Ignition (Test Methods C114)Loss
16、 on igni-tion of aggregates, consisting of end products of coal or cokecombustion, shall not exceed 12 %. Loss on ignition of otheraggregates shall not exceed 5 %.NOTE 2Some aggregates may contain carbonates or water of hydra-tion that contribute to loss on ignition but may not affect the quality of
17、 theproduct. Therefore, when evaluating an aggregate, consideration should begiven to the material characteristics that cause the ignition loss.5. Physical Properties5.1 Lightweight aggregate under test shall meet the follow-ing requirements:5.1.1 Clay Lumps and Friable Particles The amount ofclay l
18、umps and friable particles shall not exceed 2 % by drymass.5.1.2 GradingAggregate grading shall be by mutualagreement between interested parties. See Appendix X1 foraggregate grading guidance.5.1.3 Uniformity of GradingTo ensure reasonable unifor-mity in the gradation of successive shipments of ligh
19、tweightaggregate, fineness modulus shall be determined on samplestaken from shipments at intervals stipulated by the purchaser. Ifthe fineness modulus of the aggregate in any shipment differsby more than 7 % from that of the sample submitted foracceptance tests, the aggregate in the shipment shall b
20、erejected, unless the supplier demonstrated that it will produceconcrete of the required characteristics.5.1.4 Loose Bulk Density (Test Method C29/C29M)Theloose bulk density of lightweight aggregates shall conform tothe requirements in Table 1 using a 14 L 12 ft3 measure.5.1.5 Uniformity of Loose Bu
21、lk Density The dry loosebulk density of lightweight aggregate shipments sampled andtested shall not differ by more than 650 kg/m33 lb/ft3or7%,whichever is greater, from that of the sample submitted foracceptance tests, and shall not exceed the limits in Table 1.5.2 Concrete specimens containing ligh
22、tweight aggregateunder test shall meet the following requirements:5.2.1 PopoutsConcrete specimens prepared and tested inaccordance with 8.1 shall show no surface popouts.5.2.2 Resistance to Freezing and Thawing When re-quired, the aggregate supplier shall demonstrate by test orproven field performan
23、ce that the lightweight aggregate whenused in manufactured concrete masonry units and relatedconcrete units has the necessary resistance to freezing andthawing to perform satisfactorily in its intended use.NOTE 3Methods are available to evaluate the performance of manu-factured concrete masonry prod
24、ucts made with lightweight aggregates.For example, Test Method C1262 includes procedures for evaluatingmanufactured concrete masonry units and related concrete units, but doesnot include criteria for determining compliance. Care should be used inevaluating the results of Test Method C1262 or any oth
25、er method since theresults are affected by other characteristics of the concrete mixture inaddition to the characteristics of the lightweight aggregate, including, butnot limited to the following: cement content, cement type, admixtures, andwater content.5.2.3 Drying ShrinkageDrying shrinkage of con
26、cretespecimens prepared and tested in accordance with 8.6 shall notexceed 0.10 %.6. Sampling6.1 Sample lightweight aggregates in accordance with Prac-tice D75.6.2 Reduce sample to test sizes in accordance with PracticeC702.7. Number of Tests7.1 Tests on AggregateOne representative sample is re-quire
27、d for each test for organic impurities, staining, clay lumps,loss on ignition, grading, and bulk density.7.2 Tests on Concrete Masonry Units Three specimensare required for the test for popout materials.8. Test Methods8.1 Test for Popout MaterialsObtain test specimens byone of the following methods:
28、 (1) Whole concrete masonryunits, free of visible cracks or other structural defects; (2)Portions of concrete masonry units cut from whole units andhaving a surface area of at least 580 cm290 in.2; (3)Specimens prepared as described in 8.6. Autoclave test speci-mens in accordance with Test Method C1
29、51. Visually inspectthe autoclaved specimens for the number of popouts that havedeveloped on the surface and report the average number ofpopouts per specimen.8.2 Test for Resistance to Freezing and ThawingMaketests for resistance to freezing and thawing of manufacturedconcrete masonry units and rela
30、ted concrete units in accor-dance with Test Method C1262.8.3 GradingFollow the procedures of Test Method C136except that the mass of the test sample for fine aggregate shallbe in accordance with Table 2. The test sample for coarseTABLE 1 Maximum Bulk Density (Dry Loose) Requirements ofLightweight Ag
31、gregates for Concrete Masonry UnitsNominalSize DesignationMaximum DryLoose Bulk Densitykg/m3lb/ft3Fine aggregate4.75 mm (No. 4) to 01120 70Coarse aggregate9.5to2.36mm(38 in. to No. 8)880 55Combined fine and coarse aggregate 1040 65TABLE 2 Mass of Sieve Test Sample for Fine LightweightAggregatesNomin
32、al Bulk Density (Loose)of AggregateMass of TestSample, gkg/m3lb/ft380240 515 50240400 1525 100400560 2535 150560720 3545 200720880 4555 2508801040 5565 30010401120 6570 350C331/C331M 102aggregate shall consist of 2830 cm30.1 ft3 or more of thematerial used for determination of bulk density. Mechanic
33、alsieving of aggregate shall be for 5 min.8.4 Bulk Density (Loose) (Test Method C29/C29M)Theaggregate shall be tested in an oven-dry condition utilizing theshoveling procedure.8.5 Clay Lumps and Friable Particles in Aggregates, shallbe in accordance with Test Method C142.8.6 Shrinkage of Concrete, s
34、hall be in accordance with TestMethod C157/C157M, with the following exceptions:8.6.1 Prepare a concrete mix in the proportions of one partportland cement to six parts combined aggregates, measured bydry loose volume. Adjust the water content so as to produce aslump of 50 to 75 mm 2 to 3 in. and tho
35、roughly consolidatethe concrete in steel molds 50 by 50 by 285 mm 2 by 2 by 1114in. The surface of the concrete shall be steel-troweled.8.6.2 Cure the test specimens in a moist condition for 7 daysat a temperature of 23 6 2 C 73.5 6 3.5 F and a relativehumidity of not less than 95 %. Make the initia
36、l lengthmeasurements immediately after removal of specimens frommoist storage. Store the specimens in an atmosphere of 23 6 2C 73.5 6 3.5 F and a relative humidity of 50 6 5 % for theduration of the test. Make subsequent measurements at 28 and100 days.8.6.3 Calculate the difference in length of the
37、specimens,when removed from moist storage at an age of 7 days and at thefinal measurement at the age of 100 days, to the nearest 0.01 %of the effective gage length, and report as the drying shrinkageof the specimen. Report the average drying shrinkage of thespecimens tested as the drying shrinkage o
38、f the concrete.9. Rejection9.1 Material that fails to conform to the requirements of thisspecification shall be subject to rejection. The reason forrejection shall be reported to the producer or supplier promptlyand in writing.10. Certification10.1 When specified in the purchase order or contract, a
39、producers or suppliers certification shall be furnished to thepurchaser that the material was sampled and tested in accor-dance with this specification and has been found to meet therequirements. When specified in the purchase order or contract,a report of the test results shall be furnished.APPENDI
40、X(Nonmandatory Information)X1. AGGREGATE GRADING GUIDE FOR CONCRETE MASONRY UNITS WITH LOWER DENSITIESX1.1 Concrete masonry units with lower densities aremanufactured with lightweight aggregate, with a blend oflightweight aggregates, or a blend of lightweight and normal-weight aggregates. Because th
41、e aggregates being blended maycome from several different sources, the proper combinedaggregate grading (see Fig. X1.1 and Table X1.1) is important,and is one of the essential ingredients in producing qualityconcrete masonry units. The combined aggregate gradingrange shown optimizes the particle siz
42、e distribution which, inturn, optimizes the quality of the CMU in the following ways:X1.1.1 Compactibility and high strengths are obtained with-out excessive amounts of cementitious materials.X1.1.2 Shrinkage is reduced by maximizing aggregatepacking.X1.1.3 Water absorption and penetration are reduc
43、ed be-cause of improved compaction.X1.1.4 Resistance to freezing and thawing is improvedbecause better compaction results in fewer interconnectedvoids.FIG. X1.1 Suggested Total Aggregate GradingTABLE X1.1 Suggested Total Aggregate GradingSieve SizeAmount Retained On Each Sieve (Volume %)(see Fig. X1
44、.1 andA)9.5mm(38 in.) 0-24.75 mm (No. 4) 0-102.36 mm (No. 8) 15-351.18 mm (No. 16) 15-35600 m (No. 30) 5-20300 m (No. 50) 5-15150 m (No. 100) 5-15Pan 8-20AVolume % and mass % retained on each sieve are essentially equal when theparticle density of the retained fractions are approximately the same. V
45、olumetricanalysis of particle sizes of blended aggregates composed of aggregates ofdifferent densities is accomplished by considering the proportions of each aggre-gate.C331/C331M 103X1.2 CommentsX1.2.1 Keep particles retained on the 9.5 mm (38 in.) sieveto a minimum. (“0” is optimum.) (Refer to Let
46、ter “A” in Fig.X1.1.)X1.2.2 A uniform, fine textured surface is controlled bylimiting the material on 4.75 mm (No. 4) and 2.36 mm (No. 8)sieves. (Refer to Letter “B” in Fig. X1.1.)X1.2.3 A minimum of 8 % passing the 150 m (No. 100)sieve is desirable for green strength, moldability and compac-tion. L
47、ess than 8 % is acceptable when using mixtures withhigh cementitious material content. (Refer to Letter “C” in Fig.X1.1.)SUMMARY OF CHANGESCommittee C09 has identified the location of selected changes to this specification since the last issue,C33105, which may impact the use of this specification.
48、(Approved December 15, 2010)(1) Revised the standard as a dual units specification.ASTM 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 determination of the
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