1、Designation: C 535 09Standard Test Method forResistance to Degradation of Large-Size Coarse Aggregateby Abrasion and Impact in the Los Angeles Machine1This standard is issued under the fixed designation C 535; the number immediately following the designation indicates the year oforiginal adoption or
2、, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript 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
3、.1 This test method covers testing sizes of coarse aggregatelarger than 19 mm (34 in.) for resistance to degradation usingthe Los Angeles testing machine (Note 1).NOTE 1A procedure for testing coarse aggregate smaller than 37.5mm (112 in.) is covered in Test Method C 131.1.2 This standard does not p
4、urport 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.1.3 The values stated in SI units are to be
5、 regarded as thestandard. The inch-pound values given in parentheses are forinformation only.2. Referenced Documents2.1 ASTM Standards:2C 125 Terminology Relating to Concrete and ConcreteAggregatesC 131 Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact i
6、n the LosAngeles MachineC 136 Test Method for Sieve Analysis of Fine and CoarseAggregatesC 702 Practice for Reducing Samples of Aggregate toTesting SizeD75 Practice for Sampling AggregatesE11 Specification for Woven Wire Test Sieve Cloth andTest Sieves3. Terminology3.1 For definitions of terms used
7、in this test method, refer toTerminology C 125.4. Summary of Test Method4.1 This test is a measure of degradation of mineral aggre-gates of standard gradings resulting from a combination ofactions including abrasion or attrition, impact, and grinding ina rotating steel drum containing 12 steel spher
8、es. As the drumrotates, a shelf plate picks up the sample and the steel spheres,carrying them around until they are dropped to the oppositeside of the drum, creating an impact-crushing effect. Thecontents then roll within the drum with an abrading andgrinding action until the shelf plate picks up th
9、e sample and thesteel spheres, and the cycle is repeated. After the prescribednumber of revolutions, the contents are removed from the drumand the aggregate portion is sieved to measure the degradationas percent loss.5. Significance and Use5.1 The test has been widely used as an indicator of therela
10、tive quality or competence of various sources of aggregatehaving similar mineral compositions. The results do notautomatically permit valid comparisons to be made betweensources distinctly different in origin, composition, or structure.Assign specification limits with extreme care in considerationof
11、 available aggregate types and their performance history inspecific end uses.6. Apparatus6.1 The Los Angeles Machine shall conform to the require-ments of Test Method C 131.6.1.1 The operation and maintenance of the machine shallbe as prescribed in Test Method C 131.1This test method is under the ju
12、risdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.20 on Normal Weight Aggregates.Current edition approved July 1, 2009. Published August 2009. Originallyapproved in 1964. Last previous edition approved in 2003 as C 535 031.2For re
13、ferenced 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.1*A Summary of Changes section appears at the end of this standard.C
14、opyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 Sieves, conforming to Specification E11.6.3 BalanceA balance or scale accurate within 0.1 % oftest load over the range required for this test6.4 ChargeThe charge (Note 2) shall consis
15、t of 12 steelspheres averaging approximately 47 mm (12732 in.) in diam-eter, each having a mass between 390 and 445 g, and having atotal mass of 5000 6 25 g.NOTE 2Steel ball bearings 46.0 mm (11316 in.) and 47.6 mm (178in.) in diameter, having a mass approximately 400 and 440 g each,respectively, ar
16、e readily available. Steel spheres 46.8 mm (12732 in.) indiameter having a mass approximately 420 g may also be obtainable. Thecharge may consist of a mixture of these sizes conforming to the totalmass tolerance of 6.4.7. Sampling7.1 Obtain the field sample in accordance with PracticeD75and reduce t
17、o an adequate sample size in accordance withPractice C 702.8. Test Sample Preparation8.1 Wash the reduced sample and oven dry at 110 6 5C(230 6 9F) to substantially constant mass, separate intoindividual size fractions, and recombine to the grading of Table1 most nearly corresponding to the range of
18、 sizes in theaggregate as furnished for the work. Record the mass of thesample prior to test to the nearest 1 g.9. Procedure9.1 Place the test sample and charge in the Los Angelestesting machine and rotate the machine at 30 to 33 r/min for1000 revolutions (Note 3). After the prescribed number ofrevo
19、lutions, discharge the material from the machine and makea preliminary separation of the sample on a sieve coarser thanthe 1.70-mm (No. 12) sieve. Sieve the finer portion on a1.70-mm sieve in a manner conforming to Test Method C 136.Wash the material coarser than the 1.70-mm sieve and oven dryat 110
20、 6 5C (230 6 9F) to substantially constant mass, anddetermine the mass to the nearest1g.9.1.1 If the aggregate is essentially free of adherent coatingsand dust, the requirement for washing after the test is optional.However, in the case of referee testing, the washing procedureshall be performed. El
21、imination of washing after test willseldom reduce the measured loss by more than about 0.2 % ofthe original sample mass.NOTE 3Valuable information concerning the uniformity of the sampleunder test may be obtained by determining the loss after 200 revolutions.This loss should be determined by dry sie
22、ving the material on the1.70-mm (No. 12) sieve without washing. The ratio of the loss after 200revolutions to the loss after 1000 revolutions should not greatly exceed0.20 for material of uniform hardness. When this determination is made,take care to avoid losing any part of the sample; return the e
23、ntire sample,including the dust of fracture, to the testing machine for the final 800revolutions required to complete the test.10. Calculation10.1 Calculate the loss (the difference between the originalmass and the final mass of the test sample) as a percentage ofthe original mass of the test sample
24、 (Note 4).NOTE 4The percent loss determined by this method has no knownconsistent relationship to the percent loss for the same material whentested by Test Method C 131.11. Report11.1 Report the following information:11.2 Identification of the aggregate as to source, type, andnominal size, and11.3 G
25、rading designation from Table 1 used for the test, and11.4 Loss by abrasion and impact of the sample expressed tothe nearest 1 % by mass.12. Precision12.1 RepeatabilityBased on four replicate tests by asingle operator on one aggregate at a single laboratory usingthe same equipment, the average degra
26、dation (abrasion) loss,with a No. 1 grading was found to be 38.8 % and the standarddeviation was 1.8 %12.2 BiasNo statement is being made about the bias ofthis Test Method since there is no accepted reference materialsuitable for determining the bias of this procedure.13. Keywords13.1 abrasion; aggr
27、egate (coarse; large size); degradation;impact; Los Angeles machineTABLE 1 Gradings of Test SamplesSieve Size, mm (in.) (Square Openings) Mass of Indicated Sizes, gPassing Retained onGrading12375 (3) 63 (212) 2 500 6 50 . .63 (212) 50 (2) 2 500 6 50 . .50 (2) 37.5 (112) 5 000 6 50 5 000 6 50 .37.5 (
28、112) 25.0 (1) . 5 000 6 25 5 000 6 2525.0 (1) 19.0 (34) . . 5 000 6 25Total 10 000 6 100 10 000 6 75 10 000 6 50C535092APPENDIX(Nonmandatory Information)X1. MAINTENANCE OF SHELFX1.1 The shelf of the Los Angeles machine is subject tosevere surface wear and impact. With use, the working surfaceof the
29、shelf is peened by the balls and tends to develop a ridgeof metal parallel to and about 32 mm (114 in.) from the junctionof the shelf and the inner surface of the cylinder. If the shelf ismade from a section of rolled angle, not only may this ridgedevelop but the shelf itself may be bent longitudina
30、lly ortransversely from its proper position.X1.2 The shelf should be inspected periodically to deter-mine that it is not bent either lengthwise or from its normalradial position with respect to the cylinder. If either conditionis found, the shelf should be repaired or replaced before furthertests ar
31、e made. The influence on the test result of the ridgedeveloped by peening of the working face of the shelf is notknown. However, for uniform test conditions, it is recom-mended that the ridge be ground off if its height exceeds 0.1 in.(2 mm).SUMMARY OF CHANGESCommittee C09 has identified the locatio
32、n of selected changes to this test method since the last issue,C535031, that may impact the use of this test method. (Approved July 1, 2009)(1) Revised 12.1.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standar
33、d. 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
34、 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 Headquarters. Your comments will receive careful consideration at a meeting of theresponsible t
35、echnical 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 standard 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).C535093
