1.1 本试验方法包括用柔性壁渗透计对水饱和多孔材料的水力传导率进行实验室测量。 1.2 本试验方法将用作设计性能试验或作为评价不同土工织物的土壤/土工织物系统过滤行为的比较工具。 1.3 本试验方法可用于水力传导率小于或等于5 × 10的原状或压实土样 −2 厘米/秒。 1.4 导水率大于5 × 10土壤的过滤行为 −2 cm/s可以通过梯度比试验（试验方法 D5101 ). 1.5 以SI单位表示的值将被视为标准，尽管提供了其他单位用于信息和澄清目的。 1.6 本标准并不旨在解决与其使用相关的所有安全性问题（如果有）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践并确定法规限制的适用性。 1.7 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 本试验方法用于测量水饱和土壤/土工织物系统的水力传导率。 5.2 本试验方法将用作设计性能试验，或用作评估土工织物土壤过滤行为的比较工具。该测试方法不适用于常规（指数式）测试，因为结果将取决于所评估的具体土壤和水力条件。将测试结果用于工作规范或制造商认证是不合适的。 5.3 本试验方法适用于多孔材料对水的渗透。其他液体如化学废物的渗透可以使用类似于本试验方法中描述的程序来完成。然而，该测试方法仅在水是渗透液体时使用。 5.4 该试验方法中使用的数学概念（主要是达西定律）最初是为多孔材料内的一维层流而开发的，土壤和土工织物通常就是这种情况。当流动条件是层流和一-尺寸上，水力传导率不受水力梯度的影响。然而，当水流通过一些土壤/土工织物系统时，水力梯度的变化可能导致土壤颗粒的移动，从而改变试样的结构，从而改变土壤/土工织物系统的水力传导率。达西定律给出的数学表达式仍然适合应用于这种情况；然而，因此必须在HCR试验中仔细控制水力梯度以模拟现场条件。 5.5 该测试方法提供了在受控有效应力水平下测定水力传导率的方法。水力传导率随空隙率而变化，空隙率又随有效应力而变化。如果空隙率改变，试样的导水率可能会改变。因此，在HCR试验中必须仔细控制有效应力（即有效围压）以模拟现场条件。

1.1 This test method covers laboratory measurement of the hydraulic conductivity of water-saturated porous materials with a flexible-wall permeameter. 1.2 This test method is to be used as a design performance test or as a comparative tool for evaluating the filtration behavior of soil/geotextile systems with different geotextiles. 1.3 This test method may be used with undisturbed or compacted soil specimens that have a hydraulic conductivity less than or equal to 5 × 10 −2 cm/s. 1.4 The filtration behavior of soils with hydraulic conductivities greater than 5 × 10 −2 cm/s may be determined by the gradient ratio test (Test Method D5101 ). 1.5 The values stated in SI units are to be regarded as the standard, although other units are provided for information and clarification purposes. 1.6 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. 1.7 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 to be used for measuring the hydraulic conductivity of water-saturated soil/geotextile systems. 5.2 This test method is to be used as a design performance test, or as a comparative tool for evaluating the filtration behavior of soils with geotextiles. This test method is not intended for routine (index-style) testing, since the results will depend on the specific soil and hydraulic conditions that are evaluated. It is not appropriate to use the test results for job specifications or manufacturers’ certifications. 5.3 This test method applies to the permeation of porous materials with water. Permeation with other liquids, such as chemical wastes, can be accomplished using procedures similar to those described in this test method. However, this test method is intended to be used only when water is the permeant liquid. 5.4 The mathematical concepts (primarily Darcy’s law) used in this test method were originally developed for one-dimensional, laminar flow of water within porous materials, which is often the case with soil and geotextiles. When flow conditions are laminar and one-dimensional, the hydraulic conductivity is unaffected by hydraulic gradient. However, when flow occurs through some soil/geotextile systems, a change in hydraulic gradient could cause movement of soil particles, thereby changing the structure of the test specimen and hence, changing the hydraulic conductivity of the soil/geotextile system. The mathematical expressions given by Darcy’s law are still appropriate for application to this situation; however, it is therefore imperative that the hydraulic gradient be controlled carefully in the HCR test to simulate field conditions. 5.5 This test method provides a means of determining hydraulic conductivity at a controlled level of effective stress. Hydraulic conductivity varies with void ratio, which in turn varies with effective stress. The hydraulic conductivity of the test specimen will probably change if the void ratio is changed. It is therefore imperative that the effective stress (that is, the effective confining pressure) be controlled carefully in the HCR test to simulate field conditions.