Historical
ASTM D6780/D6780M-12
Standard Test Method for Water Content and Density of Soil In situ by Time Domain Reflectometry (TDR)
1.1 This test method may be used to determine the water content of soils and the in situ density of soils using a TDR apparatus.
1.2 This 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.
1.3 This test method is suitable for use as a means of acceptance for compacted fill or embankments.
1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.
1.6 Two alternative procedures are provided.
1.6.1 Procedure A involves two tests in the field, an in situ test and a test in a mold containing material excavated from the in situ test location. The apparent dielectric constant is determined in both tests.
1.6.2 Procedure B involves only an in situ test by incorporating the first voltage drop and long term voltage (V1 and Vf ) in addition to the apparent dielectric constant. While the bulk electrical conductivity can be determined from these measurements, it is not needed for the determination of water content and density.
1.7 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 IEEE/ASTM SI10-2010.
1.8 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.
ASTM International [astm]