Standard Test Method for Density of Soil and Rock In-Place at Depths Below Surface by Nuclear Methods

Importancia y uso:

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

5.6.1 For materials of densities higher than that of about the density of water, higher count rates within the same soil type relate to lower densities and, conversely, lower count rates within the same soil type relate to higher densities.

5.6.2 For materials of densities lower than the density of water, higher count rates within the same soil type relate to higher densities and, conversely, lower count rates within the same soil type relate to lower densities.

5.6.3 Because of the functional inflection of probe response for densities near the density of water, exercise great care when drawing conclusions from probe response in this density range.

Note 1: The quality of the result produced by this standard test method is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection, and the like. Users of this test method are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.

Subcomité:

D18.08

Referida por:

D5220_D5220M-21, D7277-16R23, D6031_D6031M-24, D0420-18

Volúmen:

04.08

Número ICS:

93.020 (Earth works. Excavations. Foundation construction. Underground works)

Palabras clave:

depth probe; in-place density; in situ density; nuclear methods;