1.1 本试验方法涵盖了使用冲击机复制已装载船运集装箱、圆柱形集装箱以及袋子和麻袋垂直跌落影响的一般程序。 1.2 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.3 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。 1.4 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。 ====意义和用途====== 4.1 运输集装箱和内部包装材料用于保护其内容物免受搬运、运输和储存过程中遇到的危险。休克是这些危险中比较麻烦的一种。 自由落体跌落试验虽然易于进行，但通常会使试样承受不垂直于跌落表面的跌落，从而使试样承受较小的应力。 注1: 例如，测试表明，偏离垂直度2°的非垂直下降会导致8 % 由于冲击能量在多个轴上分散，降低了进入试样的加速度。 4. 4.1.1 冲击机的受控冲击输入为评估运输集装箱、内部包装材料和内容物承受冲击的能力提供了一种方便的方法。 具有关键元件的包装系统的模拟自由跌落测试产生了良好的结果，其中冲击脉冲的频率至少是包装系统固有频率的三倍。 4.2 与大多数机械冲击试验程序一样，冲击试验机上包装的固定可能会对试验结果产生重大影响。通常，通过在包装顶部固定某种类型的横梁，将包装牢固地固定在桌子上。应注意，此类夹具产生的任何压力应最小，尤其是当被测容器为波纹状或其他类似材料时。 4.2.1 在预期低加速度、长持续时间响应的情况下，任何夹具都可能影响包装项目的响应，并可能改变该测试方法与自由下落测试之间的任何相关性。如果需要这种相关性，则可以测试包，而无需将其直接固定到表中。请注意，在这种情况下，运输集装箱可能会从桌子上剧烈反弹，如果不进行其他控制，可能会给操作员带来安全问题。为了安全和方便，通常建议将运输集装箱固定在冲击试验机工作台上，但这种固定方式不应影响本试验方法的准确性和精密度。 注2: 自然频率高于83 Hz的刚性封装系统需要的冲击脉冲时间短于当今许多冲击机目前可用的2毫秒（标称）持续时间: 哪里: d s = 冲击脉冲持续时间，s， f s = 冲击脉冲频率，Hz，和 f p = 机组系统频率，可通过试验方法确定 D999 . 类似地，使用输入冲击脉冲持续时间为3 ms的冲击机仅在封装系统频率低于56 Hz时有效。

1.1 This test method covers the general procedures of using shock machines to replicate the effects of vertical drops of loaded shipping containers, cylindrical containers, and bags and sacks. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 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. 1.4 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. ====== Significance And Use ====== 4.1 Shipping containers and the interior packaging materials are used to protect their contents from the hazards encountered in handling, transportation, and storage. Shock is one of the more troublesome of these hazards. Free-fall drop testing, while easy to perform, often understresses the test specimen by subjecting it to drops which are not perpendicular to the dropping surface. Note 1: For example, testing has shown that non-perpendicular drops, 2° off perpendicularity, result in 8 % lower acceleration into the test specimen resulting from the impact energy dispersing in several axes. 4 4.1.1 Controlled shock input by shock machines provides a convenient method for evaluating the ability of shipping containers, interior packaging materials, and contents to withstand shocks. Simulated free-fall drop testing of package systems, which have critical elements, has produced good results where the frequency of the shock pulse is at least three times that of the package system's natural frequency. 4.2 As in most mechanical shock test procedures, fixturing of the package on the shock test machine may have significant influence on the test results. Typically, packages will be firmly held on the table by securing some type of cross member(s) across the top of the package. Care should be taken that any pressure resulting from such fixturing should be minimal, particularly when the container being tested is corrugated or some other similar material. 4.2.1 In cases where low-acceleration, long-duration responses are anticipated, any fixturing can potentially influence packaged item response and can possibly alter any correlation between this test method and free-fall drop testing. Where such correlation is desired, the package can be tested without it being fixed directly to the table. Note that in such circumstances, the shipping container can vigorously rebound from the table and can, if not otherwise controlled, present a safety problem for operators. Fixing the shipping container to the shock machine table is most often recommended for safety and convenience, but accuracy and precision of this test method should not be compromised by such fixturing. Note 2: A rigid package system with a natural frequency above 83 Hz requires a shock pulse shorter than the 2-ms (nominal) duration currently available with many of today's shock machines: where: d s = shock pulse duration, s, f s = shock pulse frequency, Hz, and f p = package system frequency, which may be determined by Test Methods D999 . Similarly, a shock machine using an input shock pulse duration of 3 ms would only be effective with package system frequencies below 56 Hz.