ASTM D7382-20 PDF Download

The ASTM D7382-20 standard is designed to determine the maximum dry unit weight of granular soils. The test methods involve using a vibrating hammer to apply a surcharge and compactive effort to the soil specimen. The results of these tests are important for assessing the compactness of a soil mass, whether it is naturally occurring or constructed as fill.

The standard emphasizes the significance of maximum dry unit weight in evaluating the state of compactness of granular soils. The compactness of soil is essential for achieving desirable engineering properties, such as shear strength, compressibility, and permeability. Laboratory compaction tests, like the ones specified in this standard, are used to determine the percent compaction and water content required for achieving the desired engineering properties during construction. These tests also help in controlling the construction process to ensure that the required unit weights and water contents are achieved.

The standard acknowledges that although percent compaction is a good indicator of compactness, the engineering properties can vary depending on the method used for compaction. It highlights that professional judgment is necessary to relate soil engineering properties to the state of compactness.

The standard also addresses some common challenges encountered in construction control, such as degradation of soil, gap-graded soils, and gravelly soils with low angularity and a high percentage of fines. It provides solutions to these challenges, such as using a test fill to determine the required degree of compaction and method specification to control compaction.

It is important to note that the quality of the results obtained from this standard depends on the competence of the personnel performing the test, as well as the suitability of the equipment and facilities used. Compliance with other relevant ASTM practices does not guarantee reliable results, as many factors can affect the accuracy of the test.