1.1本试验方法包括使用称为时域反射法（TDR）的电磁技术测定土壤中的含水量（或含水量）。 1.2本试验方法旨在详细说明土壤常规TDR测量的程序。其他TDR应用是为了量化土壤中的水分含量，此处不作介绍，例如平探头技术和湿润锋推进方法。 1.3现有的商业TDR应用程序自动化了TDR方法，本测试方法中没有详细说明。与此应用方法相比，自动化商业系统中可能存在重叠，并且鼓励用户在适用时遵循此测试方法。 1.4本试验方法是包气带表征方法系列之一。已经制定了关于渗流区表征技术的其他标准。 1.5 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和健康实践，并确定监管限制的适用性。 ====意义和用途====== 土壤含水量或含水量的测定是土壤物理和水文学学科的基本需求之一。需要确定最佳灌溉时间、渗透率和土壤- 水分通量、污染物传输速率，以及评估废物场地或表面或地下屏障的泄漏可能性。 本试验方法中涵盖的TDR应用用于土壤含水量的点测量。该应用程序可以通过手动插入土壤或将探头埋在地下以获取特定位置的含水量数据。此外，可以在钻孔现场使用TDR测试岩芯样本，以获取实时土壤水分数据。

1.1 This test method covers the determination of water content (or moisture content) in soil by the use of the electromagnetic technique called Time-Domain Reflectometry (TDR). 1.2 This test method was written to detail the procedure for conventional TDR measurements of soil. Other TDR applications exist for the purpose of quantifying water content in soil and are not covered here, such as flat probe technologies and wetting front advance methods. 1.3 Commercial TDR applications exist which automate the TDR methodology and are not detailed in this test method. It is likely that overlap exists in the automated commercial systems versus this applied method, and the user is encouraged to adhere to this test method when applicable. 1.4 This test method is one of a series on vadose zone characterization methods. Other standards have been prepared on vadose zone characterization techniques. 1.5 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 and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== The determination of the water-content, or moisture content, of soil is one of the fundamental needs in the soil physics and hydrology disciplines. The need arises from requirements for defining the optimal time for irrigation, the infiltration rate, the soil-moisture flux, contaminant transport rates, and evaluating the potential for leakage from a waste site or a surface or subsurface barrier. The TDR application covered in this test method is that used for point measurements of moisture content in soil. The application is either through manual insertion into the soil or by burying a probe in the subsurface to acquire moisture content data at a specific location. In addition, core samples may be tested with TDR at a drill site to acquire real-time soil moisture data.