ASTM D5195-21

5.1?This test method is useful as a rapid, nondestructive technique for the calculation of the in-place density of soil and rock at desired depths below the surface as opposed to surface measurements in accordance with Test Method D6938. Alternative destructive methods are likewise described in this test method.

5.2?This test method is useful for informational and research purposes, only to be used for quality control and acceptance testing when correlated to other accepted methods such as Test Method D2937.

5.3?The non-destructive nature of the test method allows repetitive measurements to be made at a single test location for statistical analysis and to monitor changes over time.

5.4?The fundamental assumptions inherent in this test method are that Compton scattering and photoelectric absorption are the dominant interactions of the gamma rays with the material under test.

5.5?The probe response, in counts, may be converted to wet density by comparing the detected rate of gamma radiation with previously established calibration data (see Annex A1).

5.6?The probe count response may also be utilized directly for unitless, relative comparison with other probe readings

1.1?This test method covers the calculation of the wet density of soil and rock by the attenuation of gamma radiation, where the gamma source and the gamma detector are placed at the desired depth in a bored hole, typically lined by an access tube.

1.2?The wet density, in mass per unit volume of the material under test, is calculated by comparing the detected rate of gamma radiation with previously established calibration data (see Annex A1).

1.3?UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. Within the text of this standard, SI units appear first followed by the inch-pound (or other non-SI) units in brackets.

1.4?All observed and calculated values shall conform to the guide for significant digits and rounding established in Practice D6026.

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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6?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.