1.1 本试验方法包括在平行板荷载条件下测定热塑性管壁段的荷载-挠度行为。 注1: 这些不是全管段测试，而是管壁段测试。根据试验方法，这些试验的结果将不同于管道刚度试验 D2412 ，尽管它们可能是成比例的。该试验提供了完全不同的信息，包括恒定应变下的应力松弛，以及不同管壁设计或材料的功能和刚度比较。 1.2 本试验方法包括测定热塑性塑料壁刚度的载荷试验- 弯曲和压缩组合荷载下的管壁。也可以确定负载下管壁轮廓几何形状的变化。 1.3 本试验方法涵盖热塑性塑料管。 1.4 该试验方法确定的特征是墙体刚度和特定变形下轮廓墙尺寸的变化。 1.5 该试验方法确定的特征为墙体刚度、剖面墙体效率以及某些墙体构件在特定应变水平下的稳定性。 1.6 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.7 本规范的文本引用了提供解释材料的注释和脚注。这些注释和脚注（不包括表和图中的注释和脚注）不应视为本规范的要求。 1.8 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的用户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。 1.9 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。 ====意义和用途====== 5.1 通过该方法获得的热塑性塑料管壁设计在弯曲和压缩载荷下的性能可用于以下方面: 5.1.1 确定管壁截面的刚度。这是管道尺寸、壁设计、测试弧长和管道材料物理特性的函数。 5.1.2 比较各种热塑性管壁设计的特点。 5.1.3 比较各种管形塑料的特性。 5.1.4 研究热塑性塑料管道设计的尺寸、材料和变形特性之间的相互关系。 5.1.5 测量试验过程中可能发生的几个重要事件中的任何一个事件的变形和负载阻力。 5.1.6 为超大直径塑料管提供合理的质量控制/质量保证测试。 5.2 通过本试验方法获得的热塑性塑料管随时间变化的管壁刚度可用于以下方面: 5.2.1 预测初始加载后管壁在弯曲和压缩过程中的残余刚度。 5.2.2 出于设计目的，确定持续荷载下的松弛模量。 5.2.3 量化热塑性塑料材料配方对松弛模量的影响。 5.2.4 研究墙体轮廓的几何图案对松弛模量的影响。 5.3 弹簧线处与时间无关的壁厚减少可用于以下情况: 5.3.1 对于管壁刚度，量化任何材料成分和给定几何形状的所有壁剖面的效率与固体均匀厚度壁的效率。

1.1 This test method covers the determination of the load-deflection behavior of thermoplastic pipe wall sections under parallel plate loading conditions. Note 1: These are not full pipe section tests, but pipe wall segment tests. The results of these tests will be different from pipe stiffness tests per Test Method D2412 , although they may be proportional. This test provides quite different information, including stress relaxation under constant strain, and comparisons of the function and stiffness of different pipe wall designs or materials. 1.2 This test method covers a loading test for determining the wall stiffness of a thermoplastic-pipe wall under a combined load of bending and compression. Changes in pipe wall profile geometry under load may also be determined. 1.3 This test method covers thermoplastic pipe. 1.4 The characteristics determined by this test method are wall stiffness and changes in profile wall dimensions at specific deformations. 1.5 The characteristics determined by this test method are wall stiffness, profile wall efficiency, and for some wall elements stability at specific Strain levels. 1.6 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.7 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the specification. 1.8 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 and health practices and determine the applicability of regulatory limitations prior to use. 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. 1.9 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. ====== Significance And Use ====== 5.1 The performance under bending and compression load of a thermoplastic plastic pipe wall design obtained by this method can be used for the following: 5.1.1 To determine the stiffness of the pipe wall section. This is a function of the pipe dimensions, the wall design, the arc length tested, and the physical properties of the material of which the pipe is made. 5.1.2 To compare the characteristics of various thermoplastic pipe wall designs. 5.1.3 To compare the characteristics of various plastics in pipe form. 5.1.4 To study the interrelations of dimensions, materials, and deformation properties of thermoplastic pipe designs. 5.1.5 To measure the deformation and load-resistance at any of several significant events which may occur during the test. 5.1.6 To provide a reasonable quality control/quality assurance test for very large diameter plastic pipes. 5.2 The time-dependent pipe wall stiffness of a thermoplastic pipe obtained by this test method may used for the following: 5.2.1 To predict the residual stiffness of the pipe wall in bending and compression at all times after initial loading. 5.2.2 For purposes of design, to determine a modulus of relaxation under sustained loads. 5.2.3 To quantify the influence of material formulations of thermoplastics on the modulus of relaxation. 5.2.4 To study the influence of geometric patterns of wall profiles on the modulus of relaxation. 5.3 The time-independent reduction of wall thickness at springline may be used for the following: 5.3.1 For pipe wall stiffness, to quantify the efficiency of all wall profiles of any material composition and a given geometry with that of a solid uniform thickness wall.