【国外标准】 Standard Specification for Aggregates for Radiation-Shielding Concrete

This specification covers special aggregates for use in radiation-shielding concretes in which composition or high specific gravity, or both, are of prime consideration. Aggregates covered by specification include the natural mineral aggregates of either high density or high fixed water content, or both. These include aggregates that contain or consist predominately of materials such as barite, magnetite, hematite, ilmenite, and serpentine. Also included are synthetic aggregates such as iron, steel, ferrophosphorus and boron frit or other boron compounds. Fine aggregate consisting of natural or manufactured sand including high-density minerals. Coarse aggregate may consist of crushed ore, crushed stone, or synthetic products, or combinations or mixture thereof. Aggregates shall meet the required uniformity of specific gravity and fixed water content. The materials shall also meet the required chemical composition for serpentine, limonite, goethite, barite, ilmenite, hematite, magnetite, iron, ferrophosphorus, boron frit, boron carbide, calcium carbide.1.1 This specification covers special aggregates and/or high-density aggregates for use in radiation-shielding concretes in which composition or high specific gravity, or both, are of prime consideration.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 The text of this standard refers to notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of this standard.1.4 The following precautionary caveat pertains only to the test method portion, Section 9, of this specification: 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.1.5 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.