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Mechanical Analysis

Test Method

ASTM Designation: D 422, “Standard Test Method for Particle-Size Analysis of Soils”

Summary of Test Method

This test method covers the quantitative determination of the distribution of particle sizes in soils. The distribution of particle sizes larger than 75 µm (retained on the No. 200 sieve) is determined by sieving, while the distribution of particle sizes smaller than 75 µm is determined by a sedimentation process, using a hydrometer to secure the necessary data.

Minimum Sample Size

1 lb

Last Updated September 29, 2005

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