Checklist Description of Coarse Grained Soils Astm D 2488

1. Typical Name: Boulders Cobbles Gravel Sand

Add descriptive adjectives for minor constituents.

2. Gradation: Well-graded Poorly-graded (uniformly graded or gap-graded)

3. Size Distribution: Percent gravel, sand, and fines in fraction finer than 3 inches (76 mm) to nearest 5 percent.

If desired, the percentages may be stated in terms indicating a range of values, as follows: Trace: < 5% Few: 5 - 10%

Little: 15 - 25% Or, with gravel Some: 30 - 45% Or, gravelly Mostly: 50 - 100%

4. Percent Cobbles and Boulders: By volume

5. Particle size Range: Gravel — fine, coarse

6. Angularity of Coarse Material: Angular Subangular Subrounded Rounded

7. Particle Shape (if appropriate): Flat Elongated Flat and Elongated

8. Plasticity of Fines: Nonplastic Low Medium High

9. Mineralogy: Rocky type for gravel, predominant minerals in sand. Note presence of mica flakes, shaly particles, and organic materials.

10. Color: Use common terms or Munsell notation (in moist or wet condition).

11. Odor (for dark-colored or unusual soils only): None Earthy Organic

12. Moisture content: Dry Moist Wet

13. Natural Density: Loose Dense

14. Structure: Stratified Lensed Nonstratified

15. Cementation: Weak Moderate Strong

16. Reaction (dilute with HCL): None Weak Strong (or pH)

17. Geologic Origin: Examples - Alluvium, Residuum, Colluvium, Glacial till, Outwash, Dune sand, Alluvial fan, Talus

18. Unified Soil Classification Symbol: Estimate. (See Field Identification of Coarse-grained Soils below.) Note: Refer to tables 1 through 11 for criteria for describing many of these factors.

Copyright ASTM. Reprinted with permission.

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