【国外标准】 Standard Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine

5.1 This test has been widely used as an indicator of the relative quality or competence of various sources of aggregate having similar mineral compositions. The results do not automatically permit valid comparisons to be made between sources distinctly different in origin, composition, or structure. Assign specification limits with extreme care in consideration of available aggregate types and their performance history in specific end uses. The percent loss determined by this test method has no known consistent relationship to the percent loss for the same material when tested by Test Method C535.1.1 This test method covers a procedure for testing of coarse aggregates with a maximum size smaller than 37.5 mm ([11/2 in.] for resistance to degradation using the Los Angeles testing machine (Note 1).NOTE 1: A procedure for testing coarse aggregate larger than 19.0 mm [3/4 in.] is covered in Test Method C535. Thus coarse aggregates with a maximum size between 19 mm [3/4 in.] and 37.5 mm [11/2 in.] may be tested by Test Method C535 or Test Method C131/C131M.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.NOTE 2: Sieve size is identified by its standard designation in Specification E11. The Alternative designation given in parentheses is for information only and does not represent a different standard sieve size.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.