【国外标准】 Standard Classification for Sizes of Aggregate for Road and Bridge Construction

4.1 Some contract documents specify certain aggregate sizes for specific uses or may suggest one or more of these sizes as appropriate for the preparation of various end-product mixtures. In some cases, closer limits on variability of the aggregate grading are required.1.1 This classification defines aggregate size number designations and standard size ranges for mechanical sieve analyses of coarse aggregate and screenings for use in the construction and maintenance of various types of highways and bridges.1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.NOTE 1: 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 The text of this classification 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 classification.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.