1.1 本规范涵盖用于新一批预拌混凝土的新拌混凝土。对退回的新浇混凝土的要求应符合下文规定或买方规定。在任何情况下，如果买方的要求与本规范中的要求不同，应以买方的要求为准。本规范不包括交付给买方后混凝土的浇筑、固结、养护或保护。 1.2 本规范本身不允许混凝土生产商在新一批混凝土中使用退回的新拌混凝土。 注1: 使用退回的新浇混凝土的许可可在采购文件中提及，采购文件可参考本规范。 1.3 数量小于450 kg[1000 lb]或0.2 m的返回新浇混凝土 3. [0.25码 3. ]不受本规范的约束。 1.4 以国际单位制或英寸磅单位表示的数值应单独视为标准。每个系统中规定的值可能不是完全相等的；因此，每个系统应独立使用。将两个系统的值结合起来可能会导致不符合标准。 1.5 本标准的文本引用了提供解释性信息的注释和脚注。这些注释和脚注不应被视为本标准的要求。 1.6 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 （警告——新鲜的水硬性胶结混合物具有腐蚀性，长期使用可能会对皮肤和组织造成化学灼伤。 2. ) 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。

1.1 This specification covers returned fresh concrete for use in a new batch of ready-mixed concrete. Requirements for returned fresh concrete shall be either as hereinafter specified or as specified by the purchaser. In any case where the requirements of the purchaser differ from those in this specification, the purchaser’s requirements shall govern. This specification does not cover the placement, consolidation, curing, or protection of the concrete after delivery to the purchaser. 1.2 This specification by itself shall not grant permission to the concrete producer to use returned fresh concrete in a new batch of concrete. Note 1: The permission to use returned fresh concrete may be addressed in purchase documents, which may reference this specification. 1.3 Returned fresh concrete in a quantity of less than 450 kg [1000 lb] or 0.2 m 3 [0.25 yd 3 ] shall not be subject to this specification. 1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard. 1.5 The text of this standard references notes and footnotes, which provide explanatory information. These notes and footnotes shall not be considered as requirements of the standard. 1.6 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. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged use. 2 ) 1.7 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.