编制本标准是为了使设计工程师能够确定石棉水泥输送管的正确压力分类，以便在各种内部压力（静态、运行和浪涌）和外部荷载（土壤和叠加活荷载）组合下使用。包括描述静水荷载和外部荷载能力之间关系的组合荷载曲线，以加快选择正确的管道强度分类。

This standard has been prepared so that design engineers may determine the correct pressure classification of asbestos cement transmission pipe to use under various combinations of internal pressure (static, operating, and surge) and external load (earth and superimposed live loads). Combined loading curves depicting the relationship between hydrostatic loading and external loading capabilities are included to expedite the selection of the correct pipe strength classification.