36.1.3.1. Constant head test

Try these first

1. 1.

   What is the main purpose of the constant head test?

   Hint

   Think about the types of soils involved.

2. 2.

   Name one type of soil suitable for the constant head test.

   Hint

   Consider what types of soil have larger particles.

3. 3.

   What does the constant head test measure?

   • Soil density
   • Water retention
   • Soil permeability

   Hint

   Think about water movement in soil.

4. 4.

   True or False: The constant head test can be used for measuring fine-grained soils.

   • True
   • False

   Hint

   What do we know about fine-grained versus coarse-grained soil?

5. 5.

   A soil sample has a permeability coefficient (k) of 0.02 m/s. If water flows through the sample at a constant hydraulic head of 1 meter, how much water will flow through a 1 square meter area in one hour?

   Hint

   Consider the conversion between seconds and hours in your calculation.

6. 6.

   A constant head test is done on a soil which reveals a flow of 0.5 m³ in 10 minutes at a head of 1 m. If the cross-sectional area was 0.1 m², calculate the coefficient of permeability.

   Hint

   Convert time from minutes to seconds as needed for your calculations.