1.1 本试验方法包括适用于确定土工织物在单向流动条件下与各种类型的水饱和土壤的兼容性的性能试验。 1.2 根据土壤类型，可以使用两种评估方法来研究土工织物的过滤行为: 1.2.1 对于塑性指数低于5的土壤，应根据本标准评估系统兼容性。 1.2.2 对于塑性指数为5或以上的土壤，建议使用试验方法 D5567 （“HCR”，“导水率”）代替该试验方法。 1.2.3 如果土壤的塑性指数接近5，相关方应在进行试验前就适当方法的选择达成一致。这项任务可能需要将土工织物系统的渗透性与所使用的HCR和梯度比测试（GRT）测试设备的检测极限进行比较。 1.3 以国际单位制表示的数值应视为标准。括号中的值仅供参考。 1.4 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。 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====== 5.1 推荐使用此试验方法来评估水饱和土壤的性能- 单向流动条件下的土工布系统。所获得的结果可用于指示土壤-土工织物系统在颗粒截留和流动能力方面的兼容性。 5.2 该测试方法旨在评估项目设计阶段特定现场土壤和土工织物的性能，或提供有助于确定故障原因（例如堵塞、颗粒损失）的定性数据。土工织物的验收试验不适用。将此测试结果用于工作规范或制造商认证也是不合适的。 5.3 本试验方法适用于特定地点的调查，因此不是土工布的指数特性，因此不应要求土工布制造商或供应商。

1.1 This test method covers performance tests applicable for determining the compatibility of geotextiles with various types of water-saturated soils under unidirectional flow conditions. 1.2 Two evaluation methods may be used to investigate soil-geotextile filtration behavior, depending on the soil type: 1.2.1 For soils with a plasticity index lower than 5, the systems compatibility shall be evaluated per this standard. 1.2.2 For soils with a plasticity index of 5 or more, it is recommended to use Test Method D5567 (‘HCR,’ Hydraulic Conductivity Ratio) instead of this test method. 1.2.3 If the plasticity index of the soil is close to 5, the involved parties shall agree on the selection of the appropriate method prior to conducting the test. This task may require comparison of the permeability of the soil-geotextile system to the detection limits of the HCR and Gradient Ratio Test (GRT) test apparatus being used. 1.3 The values stated in SI units are to be regarded as standard. The values 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. 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 ====== 5.1 This test method is recommended for the evaluation of the performance of water-saturated soil-geotextile systems under unidirectional flow conditions. The results obtained may be used as an indication of the compatibility of the soil-geotextile system with respect to both particle retention and flow capacity. 5.2 This test method is intended to evaluate the performance of specific on-site soils and geotextiles at the design stage of a project, or to provide qualitative data that may help identify causes of failure (for example, clogging, particle loss). It is not appropriate for acceptance testing of geotextiles. It is also improper to utilize the results from this test for job specifications or manufacturers' certifications. 5.3 This test method is intended for site-specific investigation therefore is not an index property of the geotextile, and thus is not intended to be requested of the manufacturer or supplier of the geotextile.