1.1 本规范涵盖用于涵洞施工和雨水输送的单室预制传统钢筋混凝土三面结构。 1.2 已开发出与规范C1504配套的完整度量标准——C1504M；因此，本规范中未提供公制等效值。 注1: 本规范主要是制造和采购规范。本产品的成功性能取决于几何截面、垫层、回填的正确选择，以及安装是否符合施工规范。此处规定的预制钢筋混凝土三面结构的买方应注意，荷载条件和现场要求与规定的几何截面以及施工现场检查的规定之间应有适当的相关性。 1.3 以英寸-磅为单位的数值应视为标准值。本标准不包括其他计量单位。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）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》中确立的国际公认标准化原则制定的。

1.1 This specification covers single-cell precast conventionally reinforced concrete three-sided structures intended to be used for the construction of culverts and for the conveyance of storm water. 1.2 A complete metric companion to Specification C1504 has been developed—C1504M; therefore, no metric equivalents are presented in this specification. Note 1: This specification is primarily a manufacturing and purchasing specification. The successful performance of this product depends upon the proper selection of the geometric section, bedding, backfill, and care that the installation conforms to the construction specifications. The purchaser of the precast reinforced concrete three-sided structure specified herein is cautioned that proper correlation of the loading conditions and the field requirements with the geometric section specified and provisions for inspection at the construction site are required. 1.3 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard. 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.