1、Designation: C331/C331M 10C331/C331M 14Standard 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
2、year of last 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 intended for use in concrete masonry units when a prime cons
3、ideration isto reduce the density of the units.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from
4、thetwo systems may result in non-conformance with the standard. Some values have only SI units because the inch-pound equivalentsare not used in practice.NOTE 1Sieve size is identified by its standard designation in Specification E11. The alternative designation given in parentheses is for informati
5、ononly and does not represent a different standard sieve size.1.3 The text of this specification references notes and footnotes which provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be considered as requirements of the standard.2. Referenced D
6、ocuments2.1 ASTM Standards:2C29/C29M Test Method for Bulk Density (“Unit Weight”) and Voids in AggregateC40 Test Method for Organic Impurities in Fine Aggregates for ConcreteC114 Test Methods for Chemical Analysis of Hydraulic CementC136 Test Method for Sieve Analysis of Fine and Coarse AggregatesC1
7、42 Test Method for Clay Lumps and Friable Particles in AggregatesC151 Test Method for Autoclave Expansion of Hydraulic CementC157/C157M Test Method for Length Change of Hardened Hydraulic-Cement Mortar and ConcreteC641 Test Method for Iron Staining Materials in Lightweight Concrete AggregatesC702 Pr
8、actice for Reducing Samples of Aggregate to Testing SizeC1262 Test Method for Evaluating the Freeze-Thaw Durability of Dry-Cast Segmental Retaining Wall Units and RelatedConcrete UnitsD75 Practice for Sampling AggregatesE11 Specification for Woven Wire Test Sieve Cloth and Test Sieves3. Aggregate Ty
9、pes3.1 Three general types of lightweight aggregates are covered by this specification, as follows:3.1.1 Aggregates prepared by expanding, pelletizing, or sintering products such as blast-furnace slag, clay, diatomite, fly ash,shale, or slate, and3.1.2 Aggregates prepared by processing natural mater
10、ials, such as pumice, scoria, or tuff, and3.1.3 Aggregates consisting of end products of coal or coke combustion.3.2 The aggregates shall be composed predominately of lightweight-cellular and granular inorganic material.4. Chemical Composition4.1 Lightweight aggregates shall not contain excessive am
11、ounts of deleterious substances, as determined by the followinglimits:1 This specification is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.21 onLightweight Aggregates and Concrete.Current edition approved Dec. 1
12、5, 2010April 15, 2014. Published January 2011May 2014. Originally approved in 1953. Last previous edition approved in 20052010 asC33105.10. DOI: 10.1520/C0331_C0331M-10.10.1520/C0331_C0331M-14.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at ser
13、viceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version.
14、 Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section
15、appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.1.1 Organic Impurities (Test Method C40)Lightweight aggregates subjected to the test for organic impurities that producea color darker than the stand
16、ard shall be rejected, unless it is demonstrated that the discoloration is due to small quantities ofmaterials not harmful to the concrete.4.1.2 Staining (Test Method C641)An aggregate producing a stain index of 60 or higher shall be rejected when the depositedstain is found upon chemical analysis t
17、o contain an iron content, expressed as Fe2O3 equal to or greater than 1.5 mg/200 g ofsample.4.1.3 Loss on Ignition (Test Methods C114)Loss on ignition of aggregates, consisting of end products of coal or cokecombustion, shall not exceed 12 %. Loss on ignition of other aggregates shall not exceed 5
18、%.NOTE 2Some aggregates may contain carbonates or water of hydration that contribute to loss on ignition but may not affect the quality of the product.Therefore, when evaluating an aggregate, consideration should be given to the material characteristics that cause the ignition loss.5. Physical Prope
19、rties5.1 Lightweight aggregate under test shall meet the following requirements:5.1.1 Clay Lumps and Friable ParticlesThe amount of clay lumps and friable particles shall not exceed 2 % by dry mass.5.1.2 GradingAggregate grading shall be by mutual agreement between interested parties. See Appendix X
20、1 for aggregategrading guidance.5.1.3 Uniformity of GradingTo ensure reasonable uniformity in the gradation of successive shipments of lightweightaggregate, fineness modulus shall be determined on samples taken from shipments at intervals stipulated by the purchaser. If thefineness modulus of the ag
21、gregate in any shipment differs by more than 7 % from that of the sample submitted for acceptance tests,the aggregate in the shipment shall be rejected, unless the supplier demonstrated that it will produce concrete of the requiredcharacteristics.5.1.4 Loose Bulk Density (Test Method C29/C29M)The lo
22、ose bulk density of lightweight aggregates shall conform to therequirements in Table 1 using a 14 L 12 ft3 measure.5.1.5 Uniformity of Loose Bulk DensityThe dry loose bulk density of lightweight aggregate shipments sampled and testedshall not differ by more than 650 kg/m3 3 lb/ft3 or 7 %, whichever
23、is greater, from that of the sample submitted for acceptancetests, and shall not exceed the limits in Table 1.5.2 Concrete specimens containing lightweight aggregate under test shall meet the following requirements:5.2.1 PopoutsConcrete specimens prepared and tested in accordance with 8.1 shall show
24、 no surface popouts.5.2.2 Resistance to Freezing and ThawingWhen required, the aggregate supplier shall demonstrate by test or proven fieldperformance that the lightweight aggregate when used in manufactured concrete masonry units and related concrete units has thenecessary resistance to freezing an
25、d thawing to perform satisfactorily in its intended use.NOTE 3Methods are available to evaluate the performance of manufactured concrete masonry products made with lightweight aggregates. Forexample, Test Method C1262 includes procedures for evaluating manufactured concrete masonry units and related
26、 concrete units, but does not includecriteria for determining compliance. Care should be used in evaluating the results of Test Method C1262 or any other method since the results are affectedby other characteristics of the concrete mixture in addition to the characteristics of the lightweight aggreg
27、ate, including, but not limited to the following:cement content, cement type, admixtures, and water content.5.2.3 Drying ShrinkageDrying shrinkage of concrete specimens prepared and tested in accordance with 8.6 shall not exceed0.10 %.6. Sampling6.1 Sample lightweight aggregates in accordance with P
28、ractice D75.6.2 Reduce sample to test sizes in accordance with Practice C702.7. Number of Tests7.1 Tests on AggregateOne representative sample is required for each test for organic impurities, staining, clay lumps, losson ignition, grading, and bulk density.7.2 Tests on Concrete Masonry UnitsThree s
29、pecimens are required for the test for popout materials.TABLE 1 Maximum Bulk Density (Dry Loose) Requirements ofLightweight Aggregates for Concrete Masonry UnitsNominalSize DesignationMaximum DryLoose Bulk Densitykg/m3 lb/ft3Fine aggregate4.75 mm (No. 4) to 01120 70Coarse aggregate9.5 to 2.36 mm (38
30、 in. to No. 8)880 55Combined fine and coarse aggregate 1040 65C331/C331M 1428. Test Methods8.1 Test for Popout MaterialsObtain test specimens by one of the following methods: (1) Whole concrete masonry units, freeof visible cracks or other structural defects; (2) Portions of concrete masonry units c
31、ut from whole units and having a surface areaof at least 580 cm 2 90 in.2; (3) Specimens prepared as described in 8.6.Autoclave test specimens in accordance with Test MethodC151. Visually inspect the autoclaved specimens for the number of popouts that have developed on the surface and report theaver
32、age number of popouts per specimen.8.2 Test for Resistance to Freezing and ThawingMake tests Test for resistance to freezing and thawing of manufacturedconcrete masonry units and related concrete units in accordance with Test Method C1262.8.3 GradingFollow the procedures of Test Method C136 except t
33、hat the mass of the test sample for fine aggregate shall bein accordance with Table 2. The test sample for coarse aggregate shall consist of 2830 cm3 0.1 ft 3 or more of the material usedfor determination of bulk density. Mechanical sieving of aggregate shall be for 5 min.8.4 Bulk Density (Loose) (T
34、est Method C29/C29M)The aggregate shall be tested in an oven-dry condition utilizing theshoveling procedure.8.5 Clay Lumps and Friable Particles in Aggregates, shall be in accordance with Test Method C142.8.6 Shrinkage of Concrete, shall be in accordance with Test Method C157/C157M, with the followi
35、ng exceptions:8.6.1 Prepare a concrete mix in the proportions of one part portland cement to six parts combined aggregates, measured by dryloose volume.Adjust the water content so as to produce a slump of 50 to 75 mm 2 to 3 in. and thoroughly consolidate the concretein steel molds 50 by 50 by 285 mm
36、 2 by 2 by 1114 in. The surface of the concrete shall be steel-troweled.8.6.2 Cure the test specimens in a moist condition for 7 days at a temperature of 23 6 2 C 73.5 6 3.5 F and a relativehumidity of not less than 95 %. Make the initial length measurements immediately after removal of specimens fr
37、om moist storage.Store the specimens in an atmosphere of 23 6 2 C 73.5 6 3.5 F and a relative humidity of 50 6 5 % for the duration of thetest. Make subsequent measurements at 28 and 100 days.8.6.3 Calculate the difference in length of the specimens, when removed from moist storage at an age of 7 da
38、ys and at the finalmeasurement at the age of 100 days, to the nearest 0.01 % of the effective gage length, and report as the drying shrinkage of thespecimen. Report the average drying shrinkage of the specimens tested as the drying shrinkage of the concrete.9. Rejection9.1 Material that fails to con
39、form to the requirements of this specification shall be subject to rejection. The reason for rejectionshall be reported to the producer or supplier promptly and in writing.10. Certification10.1 When specified in the purchase order or contract, a producers or suppliers certification shall be furnishe
40、d to the purchaserthat the material was sampled and tested in accordance with this specification and has been found to meet the requirements. Whenspecified in the purchase order or contract, a report of the test results shall be furnished.APPENDIX(Nonmandatory Information)X1. AGGREGATE GRADING GUIDE
41、 FOR CONCRETE MASONRY UNITS WITH LOWER DENSITIESX1.1 Concrete masonry units with lower densities are manufactured with lightweight aggregate, with a blend of lightweightaggregates, or a blend of lightweight and normalweight aggregates. Because the aggregates being blended may come from severaldiffer
42、ent sources, the proper combined aggregate grading (see Fig. X1.1 and Table X1.1) is important, and is one of the essentialTABLE 2 Mass of Sieve Test Sample for Fine LightweightAggregatesNominal Bulk Density (Loose)of Aggregate Mass of TestSample, gkg/m3 lb/ft380240 515 50240400 1525 100400560 2535
43、150560720 3545 200720880 4555 2508801040 5565 30010401120 6570 350C331/C331M 143ingredients in producing quality concrete masonry units. The combined aggregate grading range shown optimizes the particle sizedistribution which, in turn, optimizes the quality of the CMU in the following ways:X1.1.1 Co
44、mpactibility and high strengths are obtained without excessive amounts of cementitious materials.X1.1.2 Shrinkage is reduced by maximizing aggregate packing.X1.1.3 Water absorption and penetration are reduced because of improved compaction.X1.1.4 Resistance to freezing and thawing is improved becaus
45、e better compaction results in fewer interconnected voids.X1.2 CommentsX1.2.1 Keep particles retained on the 9.5 mm (38 in.) sieve to a minimum. (“0” is optimum.) (Refer to Letter “A” in Fig. X1.1.)X1.2.2 A uniform, fine textured surface is controlled by limiting the material on 4.75 mm (No. 4) and
46、2.36 mm (No. 8) sieves.(Refer to Letter “B” in Fig. X1.1.)FIG. X1.1 Suggested Total Aggregate GradingTABLE X1.1 Suggested Total Aggregate GradingSieve Size Amount Retained On Each Sieve (Volume %)(see Fig. X1.1 and A )9.5 mm (38 in.) 0-24.75 mm (No. 4) 0-102.36 mm (No. 8) 15-351.18 mm (No. 16) 15-35
47、600 m (No. 30) 5-20300 m (No. 50) 5-15150 m (No. 100) 5-15Pan 8-20A Volume % and mass % retained on each sieve are essentially equal when theparticle density of the retained fractions are approximately the same. Volumetricanalysis of particle sizes of blended aggregates composed of aggregates ofdiff
48、erent densities is accomplished by considering the proportions of eachaggregate.C331/C331M 144X1.2.3 A minimum of 8 % passing the 150 m (No. 100) sieve is desirable for green strength, moldability and compaction. Lessthan 8 % is acceptable when using mixtures with high cementitious material content.
49、 (Refer to Letter “C” in Fig. X1.1.)C331/C331M 145SUMMARY OF CHANGESCommittee C09 has identified the location of selected changes to this specification since the last issue,C33105,10, which may impact the use of this specification. (Approved DecemberApril 15, 2010)2014)(1) Revised the standard as a dual units specification.Section 8.2.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users
