AS 1289.3.8.1:2017 PDF
Sets out the method for determining the Emerson class number of a soil. Soils are divided into seven classes on the basis of their coherence in water, with one further class being distinguished by the presence of calcium-rich minerals.
The test primarily provides a visual assessment of the behaviour of soil particles to deflocculation in water. The particle is immersed in water and the soil crumb is observed after 10 minutes and classified as to colloids in suspension. However, if the soil is dispersive, the colloid suspension will not settle after a few hours.
The test may be performed using varying water types and on oven dried or in situ samples. In adopting varying preparation methods, the test results will vary to the standard method adopted.
