2.3. Dry Unit Weight

Try these first

1. 1.

   Define dry unit weight.

   Hint

   Think about how we measure soil weight.

2. 2.

   What is a void ratio?

   Hint

   Consider the space versus the solids in the soil.

3. 3.

   What does dry unit weight measure?

   • Weight of soil solids
   • Weight of soil plus water
   • Weight of air in soil

   Hint

   Think about what 'dry' refers to.

4. 4.

   True or False: Porosity and void ratio provide the same information.

   • True
   • False

   Hint

   Evaluate how each term is defined.

5. 5.

   A soil sample has a dry unit weight of 1400 kg/m³ and a moisture content of 25%. How much weight does 1 m³ of this soil have when saturated?

   Hint

   Consider how moisture content modifies the weight.

6. 6.

   How does an increase in air voids affect the dry unit weight of soil?

   Hint

   Think about the balance between solids and voids.