General

Students practice identification of different soil samples using industry standard terminology.  Visual Classifications are different than the USCS and AASHTO classifications that depend on laboratory tests.  Instead they are used to identify soils in the field and laboratory mostly for labeling purposes.

Apparatus

Typical equipment is minimalist - identify major and minor constituents by examining the sample by eye.  In some cases a little water is used, and sometimes a small bowl is useful.

Data Sheets [right-click | "save target as" Excel 97]

Procedure

Identify source of material

Record the color

Identify major constituent - what > 50% of the material is

Identify minor constituent(s) - what the rest of the material is to the nearest 5%.

Apply descriptive terms

Note the presence of any foreign matter, such as pavement, sticks, glass or other stuff - could it be a fill material and not native earth?

Write the visual classification

 

References

Holtz, Kovaks and Sheahan (2011), section 2.9

Holtz and Kovaks (1981), pages 47-72

Gorrill (1998), page 47.

Bowles (1986), pages 65-74.

[full citations]