Soil Testing

Proctor Compaction Test

• Purpose:
  To determine the maximum dry density and optimum moisture content.
• Procedure:
  1. Compact soil in layers in a Proctor mold.
  2. Measure the weight and calculate the dry density.
  3. Repeat for varying moisture contents.
  4. Plot a graph of dry density vs. moisture content to find the peak.

Liquid Limit Test

Purpose:
To find the moisture content at which soil changes from a plastic to a liquid state.

Procedure:

1. Place soil paste in a Casagrande apparatus.
2. Cut a groove and allow the cup to drop until the groove closes.
3. Measure the moisture content.