6.4.1. Group Symbols for Coarse Soils

Try these first

1. 1.

   What does GW stand for?

   Hint

   Think about the properties of gravel.

2. 2.

   Define Liquidity Index.

   Hint

   It tells you how liquid or stiff the soil is.

3. 3.

   What does the acronym LI stand for?

   • Liquid Index
   • Liquidity Index
   • Lump Index

   Hint

   Think about what it measures.

4. 4.

   True or False: The CH symbol represents clay with high plasticity.

   • True
   • False

   Hint

   Consider the meaning of each letter in the classification.

5. 5.

   A soil sample has a plasticity index of 25, clay content of 15%, and moisture content of 30%. Classify the soil and determine its liquidity index and activity.

   Hint

   Break the problem into components: classification, then calculation.

6. 6.

   Describe how the classification of a silty soil with 52% silt content and 10% clay content would influence its use in construction compared to a clayey soil.

   Hint

   Consider how plasticity impacts construction applications.