4.2.2. Example 2

Try these first

1. 1.

   What is the dry unit weight of soil?

   Hint

   Think about how it differs from moist unit weight.

2. 2.

   What is void ratio?

   Hint

   Relate it to the concept of porosity.

3. 3.

   What is the relationship between void ratio and porosity?

   • e = n/(1-n)
   • e = 1/n
   • e = n+n

   Hint

   Consider the definitions of both terms.

4. 4.

   Specific gravity is the ratio of soil solids density to the density of water. True or False?

   • True
   • False

   Hint

   Think about how we define specific gravity in relation to water.

5. 5.

   A soil sample has a porosity of 0.43 and a dry unit weight of 1600 kg/m3. Calculate the volume of voids and the specific gravity of the soil solids.

   Hint

   Use the relationships between porosity, density, and weight.

6. 6.

   If a soil has a dry unit weight of 1400 kg/m3 and a specific gravity of 2.65, calculate its void ratio.

   Hint

   Apply the concepts of unit weight and specific gravity.