1、Designation: C 142 97 (Reapproved 2004)American Association of StateHighway and Transportation Officials StandardAASHTO No. T112Standard Test Method forClay Lumps and Friable Particles in Aggregates1This standard is issued under the fixed designation C 142; the number immediately following the desig
2、nation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by
3、 agencies of the Department of Defense.1. Scope1.1 This test method covers the approximate determinationof clay lumps and friable particles in aggregates.1.2 The values given in SI units are to be regarded as thestandard. The values given in parentheses are provided forinformation purposes only.1.3
4、This standard does not purport to address 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.2. Referenced Docum
5、ents2.1 ASTM Standards:2C 33 Specification for Concrete AggregatesC 117 Test Method for Materials Finer Than 75-m (No.200) Sieve in Mineral Aggregates by WashingC 125 Terminology Relating to Concrete and ConcreteAggregatesC 1005 Specification for Reference Masses and Devices forDetermining Mass for
6、Use in the Physical Testing ofHydraulic CementsE 11 Specification for Wire Cloth and Sieves for TestingPurposes3. Significance and Use3.1 This test method is of primary significance in determin-ing the acceptability of aggregate with respect to the require-ments of Specification C 33.4. Apparatus4.1
7、 BalanceA balance or scale accurate to within 0.1 % ofthe mass of the test sample at any point within the range of use.Balances shall conform to the accuracy of the applicablesections of Specification C 1005.4.2 ContainersRust-resistant containers of a size andshape that will permit the spreading of
8、 the sample on thebottom in a thin layer.4.3 SievesSieves conforming to Specification E 11.4.4 Drying OvenAn oven providing free circulation of airand capable of maintaining a temperature of 110 6 5C (230 69F).5. Samples5.1 Aggregate for this test method shall consist of thematerial remaining after
9、completion of testing in accordancewith Test Method C 117. To provide the quantities designatedin 5.3 and 5.4, it may be necessary to combine material frommore than one test by Test Method C 117.5.2 Dry the aggregate to substantially constant mass at atemperature of 110 6 5C (230 6 9F).5.3 Test samp
10、les of fine aggregate shall consist of theparticles coarser than a 1.18-mm (No. 16) sieve and shall havea mass not less than 25 g.5.4 Separate the test samples of coarse aggregate intodifferent sizes, using the following sieves: 4.75-mm (No. 4),9.5-mm (38-in.), 19.0-mm (34-in.), and 37.5-mm (112-in.
11、). Thetest sample shall have a mass not less than indicated in thefollowing table:Size of Particles Making UpTest SampleMass of Test Sample,min, g4.75 to 9.5-mm (No. 4 to38-in.) 10009.5 to 19.0-mm (38 to34-in.) 200019.0 to 37.5-mm (34 to 112-in.) 3000Over 37.5-mm (112-in.) 50001This test method is u
12、nder the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.20 on Normal Weight Aggregates.Current edition approved Aug. 1, 2004. Published August 2004. Originallyapproved in 1938. Last previous edition approved in 1997 as C 142
13、97.2For 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO B
14、ox C700, West Conshohocken, PA 19428-2959, United States.5.5 In the case of mixtures of fine and coarse aggregates,separate the material on the 4.75-mm (No. 4) sieve, andprepare the samples of fine and coarse aggregates in accor-dance with 5.3 and 5.4.6. Procedure6.1 Determine the mass of the test s
15、ample to the accuracyspecified in 4.1 and spread it in a thin layer on the bottom of thecontainer, cover it with distilled water, and soak it for a periodof 24 6 4 h. Roll and squeeze particles individually betweenthe thumb and forefinger to attempt to break the particle intosmaller sizes. Do not us
16、e the fingernails to break up particles,or press particles against a hard surface or each other. Classifyany particles that can be broken with the fingers into finesremovable by wet sieving as clay lumps or friable particles.After all discernible clay lumps and friable particles have beenbroken, sep
17、arate the detritus from the remainder of the sampleby wet sieving over the sieve prescribed in the following table:Size of Sieve for RemovingSize of Particles Making Up Residue of Clay Lumps andSample Friable ParticlesFine aggregate (retained on1.18-mm (No. 16) sieve)850-m (No. 20)4.75 to 9.5-mm (No
18、. 4 to38-in.) 2.36-mm (No. 8)9.5 to 19.0-mm (38 to34-in.) 4.75-mm (No. 4)19.0 to 37.5-mm (34 to 112-in.) 4.75-mm (No. 4)Over 37.5-mm (112-in.) 4.75-mm (No. 4)Perform the wet sieving by passing water over the samplethrough the sieve while manually agitating the sieve, until allundersize material has
19、been removed.6.2 Remove the retained particles carefully from the sieve,dry to substantially constant mass at a temperature of 110 65C (230 6 9F), allow to cool, and determine the mass to thenearest 0.1 % of the mass of the test sample as defined in 5.3or 5.4.7. Calculation7.1 Calculate the percent
20、of clay lumps and friable particlesin fine aggregate or individual sizes of coarse aggregate asfollows:P 5 M 2 R!/M 3 100 (1)where:P = percent of clay lumps and friable particles,M = mass of test sample (for fine aggregate the mass of theportion coarser than the 1.18-mm (No. 16) sieve asdescribed in
21、 5.3), andR = mass of particles retained on designated sieve asdetermined in accordance with 6.2.7.2 For coarse aggregates, the percent of clay lumps andfriable particles shall be an average based on the percent ofclay lumps and friable particles in each sieve size fractionweighted in accordance wit
22、h the grading of the original samplebefore separation or, preferably, the average grading of thesupply represented by the sample. Should the aggregate con-tain less than 5 % of any of the sizes specified in 6.1, that sizeshall not be tested but, for the purpose of calculating theweighted average, sh
23、all be considered to contain the samepercent of clay lumps and friable particles as the next larger ornext smaller size, whichever is present.8. Precision and Bias8.1 Precision3The estimate of the precision of this testmethod is provisional and is based on samples of one fineaggregate that was teste
24、d by ten different operators at ninedifferent laboratories. For that sample, the average “percent ofclay lumps and friable particles” in the aggregate was 1.2 %,and the standard deviation was 0.6 %. Based on this standarddeviation, the acceptable range of two test results on samplesfrom the same agg
25、regate sent to different laboratories is 1.7 %.8.2 BiasSince there is no acceptable reference materialfor determining the bias for the procedure in this test method,no statement is being made.9. Keywords9.1 aggregates; clay lumps; friable particlesASTM International takes no position respecting the
26、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 validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is
27、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 for additional standardsand should be addressed to ASTM International Head
28、quarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This sta
29、ndard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: C09-1016.C 142 97 (2004)2
