1、Designation: C637 14Standard Specification forAggregates for Radiation-Shielding Concrete1This standard is issued under the fixed designation C637; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number
2、 in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers special aggregates for use inradiation-shielding concretes in which composition or highspecific gravity, or both,
3、are of prime consideration.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 The following precautionary caveat pertains only to thetest method portion, Section 9, of this specification: Thisstandard does not purport to ad
4、dress all of the safety concerns,if any, associated with its use. It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.2. Referenced Documents2.1 ASTM Standards:2C33 Specificat
5、ion for Concrete AggregatesC125 Terminology Relating to Concrete and Concrete Ag-gregatesC127 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Coarse AggregateC128 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Fine AggregateC131 Test Met
6、hod for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the LosAngeles MachineC136 Test Method for Sieve Analysis of Fine and CoarseAggregatesC219 Terminology Relating to Hydraulic CementC535 Test Method for Resistance to Degradation of Large-Size Coarse Aggregate
7、by Abrasion and Impact in the LosAngeles MachineC638 Descriptive Nomenclature of Constituents of Aggre-gates for Radiation-Shielding Concrete3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard, refer toTerminologies C125 and C219.4. Classification4.1 Aggregates covered
8、 by this specification include:4.1.1 Natural mineral aggregates of either high density orhigh fixed water content, or both. These include aggregates thatcontain or consist predominately of materials such as barite,magnetite, hematite, ilmenite, and serpentine.4.1.2 Synthetic aggregates such as iron,
9、 steel, ferrophospho-rus and boron frit or other boron compounds (see DescriptiveNomenclature C638).4.1.3 Fine aggregate consisting of natural or manufacturedsand including high-density minerals. Coarse aggregate mayconsist of crushed ore, crushed stone, or synthetic products, orcombinations or mixt
10、ures thereof.5. Composition and Relative Density (Specific Gravity)5.1 Table 1 gives data on chemical composition and relativedensity (specific gravity) of aggregate materials covered by thisspecification.5.2 The purchaser shall specify the minimum specific grav-ity for each size and type of aggrega
11、te.5.2.1 Uniformity of Specific GravityThe relative density(specific gravity) SSD (saturated surface-dry) of successiveshipments of aggregate shall not differ by more than 3 % fromthat of the sample submitted for source approval tests. Theaverage specific gravity of the total shipment shall be equal
12、 toor greater than the specified minimum.5.3 The purchaser shall specify the minimum fixed watercontent of hydrous ores. If the design temperature, T,isdifferent from that given in 9.1.3.5, the purchaser shall specifythe value of T.5.3.1 Uniformity of Fixed Water ContentFor hydrousaggregates the fix
13、ed water content of successive shipments ofaggregate shall not be less than 95 % of the specified minimumvalue. The average fixed water content of the total shipmentshall be equal to or exceed the specified minimum value.1This specification is under the jurisdiction of ASTM Committee C09 onConcrete
14、and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.41 on Hydraulic Cement Grouts.Current edition approved June 1, 2014. Published June 2014. Originallyapproved in 1969. Last previous edition approved in 2009 as C637 09. DOI:10.1520/C0637-14.2For referenced ASTM standards, vi
15、sit 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 of this standardCopyright ASTM International,
16、100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16. Aggregate Grading6.1 Sieve AnalysisFine and coarse aggregates for conven-tionally placed concrete shall be graded within the limits givenin Specification C33, except that with the approval of thepurchaser, as much
17、 as 20 % of the material passing the 9.5-mm(38 -in.) sieve may also pass the 150-m (No. 100) sieve, withup to 10 % passing the 75-m (No. 200) sieve if the materialpassing the 75-m (No. 200) sieve is essentially free of clay orshale.6.1.1 Fine and coarse aggregates for preplaced aggregateconcrete sha
18、ll be graded according to the requirements of Table2 and as follows:Grading of AggregateRelativeDensity(SpecificGravity)of FineAggregateCoarseAggregateFineAggregateUp to 3.0 Grading 1 Grading 1Greater than3.0Grading 1 Grading 2Full range Grading 2 Grading 26.1.2 When boron frit is used as part of th
19、e fine aggregate,the grading shall be such that 100 % passes the 4.75-mm (No.4) sieve and not more than 5 % passes the 600-m (No. 30)sieve.6.2 Fineness ModulusIf the fineness modulus of the fineaggregate varies more than 0.2 from the value corresponding tothat of the sample submitted for acceptance,
20、 the fine aggregateshall be rejected unless suitable adjustments are made inconcrete proportions to compensate for the difference ingrading.7. Deleterious Substances7.1 Fine and coarse aggregates shall meet the requirementsof Specification C33.7.2 Boron frit shall not contain more than 2.0 % of wate
21、rsoluble material.NOTE 1This limit is based on concrete mixtures containing no morethan 300 kg/m3(500 lb/yd3) of boron frit.8. Abrasion Resistance of Coarse Aggregate8.1 Coarse aggregate shall have an abrasion loss not greaterthan 50 % when tested in accordance with Test Method C131,or Test Method C
22、535, as applicable. Coarse aggregate failingto meet this requirement may be used, provided it can beTABLE 1 Composition and Relative Density (Specific Gravity) of Aggregates Covered by This SpecificationPredominantConstituentClass of MaterialChemical Composition ofPrincipal ConstituentARelative Dens
23、ity(Specific Gravity) ofAvailableAggregatesSerpentineBcrushed stone, hydrous siliente Mg3Si2O5(OH)42.4to2.65LimoniteCcrushed stone, hydrous iron ore (HFeO2)x(H2O)y3.4to3.8GoethiteCcrushed stone, hydrous iron ore HFeO23.5to4.5Barite gravel or crushed stone BaSO44.0to4.4Ilmenite crushed stone, iron or
24、e FeTiO34.2to4.8Hematite crushed stone, iron ore Fe2O34.6to5.2Magnetite crushed stone, iron ore FeFe2O44.6to5.2Iron manufactured from iron/steel Fe 6.5 to 7.5FerrophosphorousDsynthetic FenP 5.8 to 6.3Boron FritEsynthetic B2O3,Al2O3,SiO2, CaO 2.6 to 2.8Boron Carbide synthetic B4C, B2O3,C 2.5Calcium B
25、oride synthetic CaB6,C 2.5AWhen it is necessary to minimize the production of long-lived secondary radiation in the shield, or to avoid using materials having inherent radioactivity, the purchasershould specify limits on the contents of objectionable elements.BThe fixed water content of serpentine r
26、anges from 10 to 13 percent by weight.CThe fixed water content of limonite and goethite ranges from 8 to 12 percent by weight.DFerrophosphorus when used in Portland cement concrete will generate flammable and possibly toxic gases which can develop high pressures if confined. SeeClendenning, T. G., K
27、ellam, B., and MacInnis, C., “Hydrogen Evolution from FerrophosphorousAggregate in Portland Cement Concrete,” Journal of theAmerican ConcreteInstitute, No. 12,December 1968. (Proceedings, Vol 65, pp. 10211028), and Mather, Bryant, discussion of Davis, Harold S., “Concrete for Radiation ShieldingInPe
28、rspective,” and closure by author in “Concrete for Nuclear Reactors,”Journal of the American Concrete Institute SP-34, Vol 1, 1972, pp. 1113.EThe fixed water content of boron frit is less than 0.5 %.TABLE 2 Grading Requirements for Coarse and Fine Aggregatesfor Preplaced Aggregate ConcreteSieve Size
29、Percentage PassingGrading 1For 37.5-mm (112 -in.)Nominal Maximum SizeAggregateGrading 2For 25-mm (1-in.) NominalMaximum SizeAggregateCoarse Aggregate50-mm (2-in.) 100 . . .37.5-mm (112 in.) 95 to 100 10025.0-mm (1-in.) 40 to 80 95 to 10019.0-mm (34 in.) 20 to 45 40 to 8012.5-mm (12-in.) 0 to 10 0 to
30、 159.5-mm (38-in.) 0to2 0to2Fine Aggregate2.36-mm (No. 8) 100 . . .1.18-mm (No. 16) 95 to 100 100600-m (No. 30) 55 to 80 75 to 95300-m (No. 50) 30 to 55 45 to 65150-m (No. 100) 10 to 30 20 to 4075-m (No. 200) 0 to 10 0 to 10Fineness modulus 1.30 to 2.10 1.00 to 1.60C637 142shown that it produces sat
31、isfactory strengths in concrete of theproportions selected for the work.9. Methods of Sampling and Testing9.1 Sample and test the aggregates in accordance with themethods cited in Specification C33 as applicable, except asfollows:9.1.1 Relative Density (Specific Gravity)Determine therelative density
32、 (specific gravity), saturated surface-dry, of fineaggregate in accordance with Test Method C128, and of coarseaggregate in accordance with Test Method C127, except thatthe mass of the test sample for fine and coarse aggregate shallbe approximately the specified mass multiplied by the ratio:relative
33、densityspecificgravity!/2.65using for relative density (specific gravity) the higher valuegiven in Table 1.9.1.2 GradingTest Method C136, except that the mass ofthe test sample for fine and coarse aggregate shall be approxi-mately the specified mass multiplied by the ratio:relativedensityspecificgra
34、vity!/2.65using for relative density (specific gravity) the higher valuegiven in Table 1.9.1.3 Fixed Water ContentWhen 90 % or more of theweight loss on ignition of the aggregate is due to fixed watercontent, determine the fixed water content, F, by the loss-on-ignition test according to 9.1.3.1. Wh
35、en less than 90 % of theloss on ignition is due to fixed water content, determine thefixed water content by the train method (9.1.3.2). In case ofdispute, use results obtained by the train method as the basisfor acceptance or rejection of the aggregate. Use the trainmethod to demonstrate that 90 % o
36、r more of the weight lostduring ignition is fixed water. When loss-on-ignition tests arebeing made on aggregate samples from the same source, alsodetermine the fixed water content of the first sample and eachtenth sample thereafter by the train method.9.1.3.1 For the loss-on-ignition test crush a re
37、presentativesample of aggregate weighing 20 to 50 g (W) to pass the4.75-mm (No. 4) sieve. Heat the sample to constant weight ata temperature, T, in a furnace, open to the atmosphere. Cool theheated sample in a desiccator and then weigh it, (Wt). Place thesample in the oven again, heat at the ignitio
38、n temperature, t,cool in a desiccator, and determine the final weight (Wt).Constant weight may be considered to have been attained whenfurther heating at the design temperature T causes or wouldcause less than 0.1 % additional weight loss.9.1.3.2 In the train test, heat approximately 1 g (W) of thef
39、inely ground sample to constant weight (WT) at a temperatureof T. Then heat the sample WTin a stream of argon gas at theignition temperature t. Pass water vapor and gaseous materialdriven from the heated sample through magnesium perchlorate.The gain in weight (Wg) of the magnesium perchlorate is ani
40、ndication of the fixed water content of the sample at tempera-ture T. Also determine the dehydrated weight (Wt) of thesample at the ignition temperature t.9.1.3.3 Compute the fixed water content at temperature T byone of the following equations:Ignition Test:F,percent 5 WT2 Wt!/WT# 3 100 (1)where:WT
41、= sample heated to constant weight, g, andWt= heated and cooled sample, g.Train Test:F,percent 5 Wg2 WT! 3 100 (2)where:Wg= gain in weight of sample, g, andWT= dehydrated weight, g.9.1.3.4 Determine the percent of nonhydrous volatilematerial, V, as follows:Train Test:V, percent 5 $W2Wt1Wg!#/WT% 3100
42、 (3)where:W = sample weight, g,Wt= dehydrated weight of sample, g,Wg= gain in weight of sample, g, andWT= sample heated to constant weight, g.9.1.3.5 Water vapor driven from the sample by heating attemperature T is considered as part of the nonhydrous volatilematerial. Absorbed water at 110C is not
43、considered as part ofthe nonhydrous volatile material. Determine percent absorptionby Test Methods C127 and C128.9.1.3.6 Temperature values shall be as follows:DesignTemperature, TIgnitionTemperature, tHydrous Aggregate C CIron ore 110 500Serpentine 300 900Heat the sample until it reaches constant w
44、eight at thespecified temperature, unless otherwise approved. Determineweights after sample has been cooled in a desiccator to roomtemperature. Duplicate determinations of fixed water contentshould check to within 0.3 %.9.1.4 Water-Soluble Material in Boron FritPlace a 5.00-gsample passing a 600-m (
45、No. 30) sieve and retained on a300-m (No. 50) sieve in contact with 100 mL of distilledwater at 20 6 5C for 16 h. Filter, wash with about 200-mL ofhot (70 6 5C) water, and dry at 125 6 10C for 1 h. Weighthe residue, s, to the nearest 0.01 g. Calculate the percentage ofwater soluble material (Ws) to
46、the nearest 0.1 % as follows:W35 5.00 2 s!/s# 3100where:s = residue, g.10. Precision and Bias10.1 PrecisionThe following precision statement ad-dresses the test of the water-soluble material in Boron Frit. Theprecision for fixed water content by either the loss on ignitiontest or by the train test m
47、ethod has not been evaluated.10.1.1 Data from one laboratory was available for estimat-ing the precision of water-soluble material in boron frit,therefore, only a within-laboratory estimate of precision isC637 143made. The estimate is based on 15 replicate analyses of 5 lotsof frit produced by one c
48、ompany. The 15 replicates weredetermined on 5 separate days, 3 replicates per day. The meanwater soluble material ranged from 1.23 to 1.75 % among the5 lots.10.1.2 Within-laboratory PrecisionThe within-laboratorystandard deviation among individual determinations of water-soluble material in boron fr
49、it is 0.224 %.3Therefore, twoanalyses of the same material should differ by no more than0.627 %3in 95 % of cases.10.2 BiasSince there is no accepted reference materialsuitable for determining the bias of this test method, nostatement on bias is made.11. Keywords11.1 aggregates; boron frit; calcium boride; high-densityaggregates; high water-content aggregates; hydrous aggre-gates; radiation shielding concreteSUMMARY OF CHANGESCommittee C09 has identified the location of selected changes to this standard since the last
