1.1 当整个横截面以相对较低的均匀应变率或加载率受压时，该试验方法涵盖了塑料木材和形状的机械性能的测定。采用“制造”形式的试样。因此，这是一种评估塑料木材或形状产品性能的测试方法，而不是材料性能测试方法。 注1: 该测试方法是为应用于塑料木材而开发的，但它足够通用，同样适用于其他塑料复合材料，包括木塑复合材料。 1.2 塑料木材和塑料型材目前主要由回收塑料制成。然而，该试验方法也适用于由原始树脂制成的类似塑料制品，或产品横截面不均匀的情况。 1.3 以英寸磅为单位的数值应视为标准。括号中给出的值仅供参考。 1.4 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。 注2: 目前还没有与此测试方法等效的ISO。 1.5 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。 ====意义和用途====== 4.1 当这些产品在接近测试条件的条件下使用时，压缩测试提供了有关塑料木材和形状的压缩性能的信息。 在某些材料的情况下，将有一个规范要求使用该测试方法，但在遵守规范时，会优先进行一些程序修改。因此，在使用本试验方法之前，建议参考该材料规范。分类中的表1 D4000 列出了当前存在的ASTM材料标准。 4.2 抗压性能包括弹性模量、割线模量、抗压强度和给定应变下的应力。在材料因粉碎性断裂而压缩失败的情况下，压缩强度具有非常确定的值。在材料在压缩过程中不会因粉碎性断裂而失效，也不会表现出压缩屈服点的情况下，压缩强度是任意的，取决于被视为表明完全失效的变形程度。许多塑料木材材料不会表现出真正的屈服点。 在这种情况下，抗压强度可能没有实际意义。对于塑料木材，给定应变为3时的应力 % （0.03英寸/英寸（mm/mm））。 4.3 压缩试验提供了一种标准的数据获取方法，用于研发、质量控制、规范下的验收或拒收以及特殊目的。在与标准测试的负载时间尺度相差甚远的应用中，这些测试不能被视为对工程设计具有重要意义。此类应用需要额外的测试，如冲击、蠕变和疲劳。

1.1 This test method covers the determination of the mechanical properties of plastic lumber and shapes, when the entire cross-section is loaded in compression at relatively low uniform rates of straining or loading. Test specimens in the “as-manufactured” form are employed. As such, this is a test method for evaluating the properties of plastic lumber or shapes as a product and not a material property test method. Note 1: This test method was developed for application to plastic lumber materials, but it is generic enough that it would be equally applicable to other plastic composite materials, including wood-plastic composite materials. 1.2 Plastic lumber and plastic shapes are currently made predominantly with recycled plastics. However, this test method would also be applicable to similar manufactured plastic products made from virgin resins, or where the product is non-homogenous in the cross-section. 1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only. 1.4 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. Note 2: There is no known ISO equivalent to this test method. 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. ====== Significance And Use ====== 4.1 Compression tests provide information about the compressive properties of plastic lumber and shapes when these products are used under conditions approximating those under which the tests are made. In the case of some materials, there will be a specification that requires the use of this test method, but with some procedural modifications that take precedence when adhering to the specification. Therefore, it is advisable to refer to that material specification before using this test method. Table 1 in Classification D4000 lists the ASTM materials standards that currently exist. 4.2 Compressive properties include modulus of elasticity, secant modulus, compressive strength, and stress at a given strain. In the case of a material that fails in compression by a shattering fracture, the compressive strength has a very definite value. In the case of a material that does not fail in compression by a shattering fracture nor exhibits a compressive yield point, the compressive strength is an arbitrary one depending upon the degree of distortion that is regarded as indicating complete failure. Many plastic lumber materials will not exhibit a true yield point. Compressive strength can have no real meaning in such cases. For plastic lumber, the stress at a given strain of 3 % (0.03 in./in. (mm/mm)) is typically used. 4.3 Compression tests provide a standard method of obtaining data for research and development, quality control, acceptance or rejection under specifications, and special purposes. The tests cannot be considered significant for engineering design in applications differing widely from the load-time scale of the standard test. Such applications require additional tests such as impact, creep, and fatigue.