ASTM D 6780/D6780M : 2019

1.1This test method may be used to determine the water content of soils and the density of soils in place using Time Domain Reflectometry.

1.2This test method applies to soils that have 30 % or less by weight of their particles retained on the 19.0-mm [³/₄-in.] sieve.

1.3This test method is suitable for use as a means of acceptance for compacted fill or embankments.

1.4This test method is not appropriate for frozen soils or soils at temperatures over 40°C [100°F] and may not be suitable for organic soils, highly plastic soils, or extremely dense soils.

1.5All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.

1.6Two alternative procedures are provided to determine the water content and the density of soil in situ:

1.7Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. For additional information consult SI10.

1.8This 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.

1.9This 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.