1、Designation: C331/C331M 17Standard 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.1. Scope*1.1 This specification covers lightweight aggregates in-tended for use in concrete masonry units when a primeconsideration is
3、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, eachsystem shall be used independently of the other. Combiningvalues from the two systems
4、 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. The alternative designation given in parentheses is forinformation only and doe
5、s 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 not beconsidered as requirements of the standard.1.4 This international standard
6、 was developed in accor-dance 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. Refer
7、enced 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 HydraulicCementC125 Terminology Relating to Concrete and Concrete Ag-gregatesC
8、136 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 Iro
9、n Staining Materials in Light-weight Concrete AggregatesC702 Practice for Reducing Samples ofAggregate to TestingSizeC1262 Test Method for Evaluating the Freeze-Thaw Dura-bility of Dry-Cast Segmental Retaining Wall Units andRelated Concrete UnitsD75 Practice for Sampling AggregatesE11 Specification
10、for Woven Wire Test Sieve Cloth and TestSieves3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this specification, referto Terminology C125.4. Aggregate Types4.1 Three general types of lightweight aggregates are cov-ered by this specification, as follows:4.1.1 Aggregates prepared
11、 by expanding, pelletizing, orsintering products such as blast-furnace slag, clay, diatomite,fly ash, shale, or slate, and4.1.2 Aggregates prepared by processing natural materials,such as pumice, scoria, or tuff, and4.1.3 Aggregates consisting of end products of coal or cokecombustion.4.2 The aggreg
12、ates shall be composed predominately oflightweight-cellular and granular inorganic material.5. Chemical Composition5.1 Lightweight aggregates shall not contain excessiveamounts of deleterious substances, as determined by thefollowing limits:1This specification is under the jurisdiction of ASTM Commi
13、ttee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.21 on Lightweight Aggregates and Concrete.Current edition approved June 15, 2017. Published July 2017. Originallyapproved in 1953. Last previous edition approved in 2014 as C331/C331M 14.DOI: 10.1520/C033
14、1_C0331M-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 ASTM website.*A Summary of Changes section appears at the end
15、of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDeve
16、lopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.15.1.1 Organic Impurities (Test Method C40)Lightweightaggregates subjected to the test for organic impurities thatproduce a color darker than the standard
17、 shall be rejected,unless it is demonstrated that the discoloration is due to smallquantities of materials not harmful to the concrete.5.1.2 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 c
18、ontain aniron content, expressed as Fe2O3equal to or greater than 1.5mg/200 g of sample.5.1.3 Loss on Ignition (Test Methods C114)Loss 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 %.NOT
19、E 2Some aggregates may contain carbonates or water of hydra-tion that contribute to loss on ignition but may not affect the quality of theproduct. Therefore, when evaluating an aggregate, consideration should begiven to the material characteristics that cause the ignition loss.6. Physical Properties
20、6.1 Lightweight aggregate under test shall meet the follow-ing requirements:6.1.1 Clay Lumps and Friable ParticlesThe amount ofclay lumps and friable particles shall not exceed 2 % by drymass.6.1.2 GradingAggregate grading shall be by mutualagreement between interested parties. See Appendix X1 forag
21、gregate grading guidance.6.1.3 Uniformity of GradingTo ensure reasonable unifor-mity in the gradation of successive shipments of lightweightaggregate, fineness modulus shall be determined on samplestaken from shipments at intervals stipulated by the purchaser. Ifthe fineness modulus of the aggregate
22、 in any shipment differsby more than 7 % from that of the sample submitted foracceptance tests, the aggregate in the shipment shall berejected, unless the supplier demonstrated that it will produceconcrete of the required characteristics.6.1.4 Loose Bulk Density (Test Method C29/C29M)Theloose bulk d
23、ensity of lightweight aggregates shall conform tothe requirements in Table 1 using a 14 L 12 ft3 measure.6.1.5 Uniformity of Loose Bulk DensityThe dry loose bulkdensity of lightweight aggregate shipments sampled and testedshall not differ by more than 650 kg/m33 lb/ft3or7%,whichever is greater, from
24、 that of the sample submitted foracceptance tests, and shall not exceed the limits in Table 1.6.2 Concrete specimens containing lightweight aggregateunder test shall meet the following requirements:6.2.1 PopoutsConcrete specimens prepared and tested inaccordance with 9.1 shall show no surface popout
25、s.6.2.2 Resistance to Freezing and ThawingWhen required,the aggregate supplier shall demonstrate by test or proven fieldperformance that the lightweight aggregate when used inmanufactured concrete masonry units and related concreteunits has the necessary resistance to freezing and thawing toperform
26、satisfactorily in its intended use.NOTE 3Methods are available to evaluate the performance of manu-factured concrete masonry products made with lightweight aggregates.For example, Test Method C1262 includes procedures for evaluatingmanufactured concrete masonry units and related concrete units, but
27、doesnot include criteria for determining compliance. Care should be used inevaluating the results of Test Method C1262 or any other method since theresults are affected by other characteristics of the concrete mixture inaddition to the characteristics of the lightweight aggregate, including, butnot
28、limited to the following: cement content, cement type, admixtures, andwater content.6.2.3 Drying ShrinkageDrying shrinkage of concretespecimens prepared and tested in accordance with 9.6 shall notexceed 0.10 %.7. Sampling7.1 Sample lightweight aggregates in accordance with Prac-tice D75.7.2 Reduce s
29、ample to test sizes in accordance with PracticeC702.8. Number of Tests8.1 Tests on AggregateOne representative sample is re-quired for each test for organic impurities, staining, clay lumps,loss on ignition, grading, and bulk density.8.2 Tests on Concrete Masonry UnitsThree specimens arerequired for
30、 the test for popout materials.9. Test Methods9.1 Test for Popout MaterialsObtain test specimens byone of the following methods: (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
31、 at least 580 cm290 in.2; (3)Specimens prepared as described in 9.6. Autoclave test speci-mens in accordance with Test Method C151. Visually inspectthe autoclaved specimens for the number of popouts that havedeveloped on the surface and report the average number ofpopouts per specimen.9.2 Test for R
32、esistance to Freezing and ThawingTest forresistance to freezing and thawing of manufactured concretemasonry units and related concrete units in accordance withTest Method C1262.9.3 GradingFollow the procedures of Test Method C136except that the mass of the test sample for fine aggregate shallbe in a
33、ccordance with Table 2. The test sample for coarseaggregate shall consist of 2830 cm30.1 ft3 or more of thematerial used for determination of bulk density. Mechanicalsieving of aggregate shall be for 5 min.TABLE 1 Maximum Bulk Density (Dry Loose) Requirements ofLightweight Aggregates for Concrete Ma
34、sonry 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 65C331/C331M 1729.4 Bulk Density (Loose) (Test Method C29/C29M)Theaggregate shall be tested in
35、an oven-dry condition utilizing theshoveling procedure.9.5 Clay Lumps and Friable Particles in Aggregates, shallbe in accordance with Test Method C142.9.6 Shrinkage of Concrete, shall be in accordance with TestMethod C157/C157M, with the following exceptions:9.6.1 Prepare a concrete mix in the propo
36、rtions 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 thoroughly consolidatethe concrete in steel molds 50 by 50 by 285 mm 2 by 2 by 1114in. The surface of the concrete shall be
37、steel-troweled.9.6.2 Cure the test specimens in a moist condition for 7 daysat a temperature of 23 6 2C 73.5 6 3.5F and a relativehumidity of not less than 95 %. Make the initial lengthmeasurements immediately after removal of specimens frommoist storage. Store the specimens in an atmosphere of 23 6
38、2C 73.5 6 3.5F and a relative humidity of 50 6 5 % for theduration of the test. Make subsequent measurements at 28 and100 days.9.6.3 Calculate the difference in length of the specimens,when removed from moist storage at an age of 7 days and at thefinal measurement at the age of 100 days, to the near
39、est 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 of the concrete.10. Rejection10.1 Material that fails to conform to the requirements ofthis specification shall be subject to
40、rejection. The reason forrejection shall be reported to the producer or supplier promptlyand in writing.11. Certification11.1 When specified in the purchase order or contract, aproducers or suppliers certification shall be furnished to thepurchaser that the material was sampled and tested in accor-d
41、ance 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.APPENDIX(Nonmandatory Information)X1. AGGREGATE GRADING GUIDE FOR CONCRETE MASONRY UNITS WITH LOWER DENSITIESX1.1 Concrete masonry
42、 units with lower densities aremanufactured with lightweight aggregate, with a blend oflightweight aggregates, or a blend of lightweight and normal-weight aggregates. Because the aggregates being blended maycome from several different sources, the proper combinedaggregate grading (see Fig. X1.1 and
43、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 size distribution which, inturn, optimizes the quality of the CMU in the following ways:X1.1.1 Compactibility and high strengt
44、hs 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 reduced be-cause of improved compaction.X1.1.4 Resistance to freezing and thawing is improvedbecause better compaction results i
45、n fewer interconnectedvoids.TABLE 2 Mass of Sieve Test Sample for Fine LightweightAggregatesNominal Bulk Density (Loose)of AggregateMass of TestSample, gkg/m3lb/ft380240 515 50240400 1525 100400560 2535 150560720 3545 200720880 4555 2508801040 5565 30010401120 6570 350FIG. X1.1 Suggested Total Aggre
46、gate GradingC331/C331M 173X1.2 CommentsX1.2.1 Keep particles retained on the 9.5 mm (38 in.) sieveto a minimum. (“0” is optimum.) (Refer to Letter “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 Le
47、tter “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. Less than 8 % is acceptable when using mixtures withhigh cementitious material content. (Refer to Letter “C” in Fig.X1.1.)SUMMARY OF CHANGESCommittee C09 has
48、identified the location of selected changes to this specification since the last issue,C331/C331M 14, which may impact the use of this specification. (Approved June 15, 2017.)(1) Added terminology section.ASTM International takes no position respecting the validity of any patent rights asserted in c
49、onnection with any item mentionedin this standard. Users of this standard 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 not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or
