1.1 本试验方法涵盖通量和导水率的实验室测量（也称为 渗透系数 )土工合成粘土衬垫（GCL）样品渗透化学溶液和浸出液，使用柔性壁渗透仪。关于土工合成粘土衬垫指数水力特性的测试测量，请参阅测试方法 D5887/D5887M . 关于土壤与水化学溶液和浸出液的导水性兼容性，请参阅测试方法 D7100 . 1.2 本试验方法可用于导水率小于或等于1的GCL试样 × 10 –5 米/秒（1 × 10 –3 厘米/秒）。 1.3 本试验方法适用于具有土工布背衬的GCL产品。它不适用于具有土工膜背衬、土工膜背衬或聚合物涂层背衬的GCL产品。 1.4 该测试方法允许请求者通过现场评估GCL的水力特性- 不同试验条件下的特定或实验室制备的溶液；因此，测试方法也可用于检查性能或一致性，或两者兼而有之。 1.5 除非特别给出了其他单位，否则以国际单位制表示的数值应视为标准。根据美国的惯例，导水率以厘米/秒为单位，尽管导水率的常用国际单位为米/秒。 1.6 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。 1.7 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 本试验方法适用于水溶液的一维层流，如化学溶液、垃圾填埋场渗滤液和受污染水（从这里开始称为“试验液”），通过在规定或要求的条件下固结和渗透的饱和/水合GCL样品。 4.2 本试验方法假设达西定律有效，导水率基本上不受水力梯度的影响。达西定律的有效性可以通过测量三种不同水力梯度下试样的导水率来评估；如果所有测量值相似（在25%左右 %), 那么可以认为达西定律是有效的。然而，当作用在试样上的水力梯度改变时，应力状态也会改变，如果试样是可压缩的，则试样的体积也会改变。 因此，当水力梯度改变时，即使在达西定律有效的情况下，导水率也可能发生一些变化。 4.3 该测试方法提供了在以下两种不同情况下确定给定GCL通量和导水率值的工具，这两种情况应由申请人指定: 4.3.1 场景1–在接触测试液体之前用水进行水合/饱和- 该场景模拟了GCL在与实际测试液体接触之前用水充分水合的现场条件。应注意的是，初始饱和度/水化程度极大地影响GCL产品的水力特性。试验分为两个阶段:（第1阶段）水合、饱和、固结和渗透水作为试验液1，（第2阶段）切换到渗透水作为试验液2。 4.3.2 场景2–用测试液体水合/饱和（最坏情况）- 该场景模拟了GCL在用水充分水合之前与测试液体接触的现场条件。应注意的是，与方案1相比，该方案可能会导致更高的通量和水力传导率值，因为试验液体中存在的化学品可能会改变GCL产品的水化和水力特性。 4.4 本试验方法中使用的仪器通常用于测定土壤样本的导水率。然而，本试验中测得的通量值通常远低于大多数天然土壤中通常测得的通量值。本试验中设备的泄漏率必须小于10 % 流量。

1.1 This test method covers laboratory measurement of both flux and hydraulic conductivity (also referred to as coefficient of permeability ) of geosynthetic clay liner (GCL) specimens permeated with chemical solutions and leachates utilizing a flexible wall permeameter. For test measurement of index hydraulic properties of geosynthetic clay liners, refer to Test Method D5887/D5887M . For hydraulic conductivity compatibility of soils with aqueous chemical solutions and leachates, refer to Test Method D7100 . 1.2 This test method may be utilized with GCL specimens that have a hydraulic conductivity less than or equal to 1 × 10 –5 m/s (1 × 10 –3 cm/s). 1.3 This test method is applicable to GCL products having geotextile backing(s). It is not applicable to GCL products with geomembrane backing(s), geofilm backing(s), or polymer coating backing(s). 1.4 This test method allows the requester to evaluate the hydraulic properties of a GCL with site-specific or laboratory-prepared solution under different test conditions; thus, the test method also may be used to check performance or conformance, or both. 1.5 The values stated in SI units are to be regarded as the standard, unless other units are specifically given. By tradition in U.S. practice, hydraulic conductivity is reported in centimeters per second, although the common SI units for hydraulic conductivity are meters per second. 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 ====== 4.1 This test method applies to one-dimensional, laminar flow of aqueous solutions, such as chemical solutions, landfill leachate, and contaminated water (from here on referred to as “test liquid”), through saturated/hydrated GCL specimen that is consolidated and permeated under a prescribed or requested set of conditions. 4.2 This test method assumes that Darcy’s law is valid and that the hydraulic conductivity is essentially unaffected by hydraulic gradient. The validity of Darcy’s law may be evaluated by measuring the hydraulic conductivity of the specimen at three different hydraulic gradients; if all measured values are similar (within about 25 %), then Darcy's law may be taken as valid. However, when the hydraulic gradient acting on a test specimen is changed, the state of stress will also change and, if the specimen is compressible, the volume of the specimen will change. Thus, some change in hydraulic conductivity may occur when the hydraulic gradient is altered, even in cases where Darcy's law is valid. 4.3 This test method provides tools for determining flux and hydraulic conductivity values for a given GCL under the following two different scenarios, which should be specified by the requester: 4.3.1 Scenario 1 – Hydrated/Saturated with Water Prior to Contact with Test Liquid— This scenario simulates the field conditions where the GCL is well hydrated with water prior to contact with actual test liquid. It should be noted that initial degree of saturation/hydration greatly affects the hydraulic properties of a GCL product. The test has two phases: (Phase 1) hydrate, saturate, consolidate, and permeate with water as Test Liquid 1, and (Phase 2) switch to permeation with test liquid as Test Liquid 2. 4.3.2 Scenario 2 – Hydrated/Saturated with Test Liquid (Worst Case)— This scenario simulates the field conditions where the GCL is in contact with test liquid prior to being fully hydrated with water. It should be noted that this scenario may result in higher flux and hydraulic conductivity values compared to Scenario 1, as chemicals present in test liquid may alter the hydration and hydraulic properties of a GCL product. 4.4 The apparatus used in this test method is commonly used to determine the hydraulic conductivity of soil specimens. However, flux values measured in this test are typically much lower than those commonly measured for most natural soils. It is essential that the leakage rate of the apparatus in this test be less than 10 % of the flux.